diff --git a/Android.mk b/Android.mk
deleted file mode 100644
index 5053e7d..0000000
--- a/Android.mk
+++ /dev/null
@@ -1 +0,0 @@
-include $(call all-subdir-makefiles)
diff --git a/core/Makefile b/core/Makefile
index 4eb04a6..f6a246b 100644
--- a/core/Makefile
+++ b/core/Makefile
@@ -122,6 +122,33 @@
 endif
 
 # -----------------------------------------------------------------
+# generate preview API fingerprint
+api_fingerprint := $(call intermediates-dir-for,PACKAGING,api_fingerprint)/api_fingerprint.txt
+.KATI_READONLY := api_fingerprint
+
+ifeq (REL,$(PLATFORM_VERSION_CODENAME))
+  $(api_fingerprint):
+	echo REL >$@
+else ifneq ($(TARGET_BUILD_APPS),)
+  # TODO: use a prebuilt api_fingerprint.txt from prebuilts/sdk/current.txt once we have one
+  #$(eval $(call copy-one-file,prebuilts/sdk/current/api_fingerprint.txt,$(api_fingerprint)))
+  $(api_fingerprint):
+	echo $(PLATFORM_PREVIEW_SDK_VERSION) >$@
+else ifneq ($(TARGET_BUILD_PDK),)
+  $(eval $(call copy-one-file,$(_pdk_fusion_intermediates)/api_fingerprint.txt,$(api_fingerprint)))
+else
+  ifeq ($(HOST_OS),darwin)
+  $(api_fingerprint): PRIVATE_HASH := md5
+  else
+  $(api_fingerprint): PRIVATE_HASH := md5sum
+  endif
+  $(api_fingerprint): $(sort $(wildcard frameworks/base/api/*current.txt))
+	cat $^ | $(PRIVATE_HASH) | cut -d' ' -f1 >$@
+
+  $(call dist-for-goals,sdk,$(api_fingerprint))
+endif
+
+# -----------------------------------------------------------------
 # property_overrides_split_enabled
 property_overrides_split_enabled :=
 ifeq ($(BOARD_PROPERTY_OVERRIDES_SPLIT_ENABLED), true)
@@ -368,7 +395,7 @@
 else
 system_prop_file := $(wildcard $(TARGET_DEVICE_DIR)/system.prop)
 endif
-$(intermediate_system_build_prop): $(BUILDINFO_SH) $(BUILDINFO_COMMON_SH) $(INTERNAL_BUILD_ID_MAKEFILE) $(BUILD_SYSTEM)/version_defaults.mk $(system_prop_file) $(INSTALLED_ANDROID_INFO_TXT_TARGET)
+$(intermediate_system_build_prop): $(BUILDINFO_SH) $(BUILDINFO_COMMON_SH) $(INTERNAL_BUILD_ID_MAKEFILE) $(BUILD_SYSTEM)/version_defaults.mk $(system_prop_file) $(INSTALLED_ANDROID_INFO_TXT_TARGET) $(api_fingerprint)
 	@echo Target buildinfo: $@
 	@mkdir -p $(dir $@)
 	$(hide) echo > $@
@@ -401,6 +428,7 @@
 	        PLATFORM_BASE_OS="$(PLATFORM_BASE_OS)" \
 	        PLATFORM_SDK_VERSION="$(PLATFORM_SDK_VERSION)" \
 	        PLATFORM_PREVIEW_SDK_VERSION="$(PLATFORM_PREVIEW_SDK_VERSION)" \
+	        PLATFORM_PREVIEW_SDK_FINGERPRINT="$$(cat $(api_fingerprint))" \
 	        PLATFORM_VERSION_CODENAME="$(PLATFORM_VERSION_CODENAME)" \
 	        PLATFORM_VERSION_ALL_CODENAMES="$(PLATFORM_VERSION_ALL_CODENAMES)" \
 	        PLATFORM_MIN_SUPPORTED_TARGET_SDK_VERSION="$(PLATFORM_MIN_SUPPORTED_TARGET_SDK_VERSION)" \
@@ -1591,12 +1619,13 @@
 $(RECOVERY_INSTALLING_TEXT_FILE): PRIVATE_IMAGE_GENERATOR_JAR := $(image_generator_jar)
 $(RECOVERY_INSTALLING_TEXT_FILE): PRIVATE_ZOPFLIPNG := $(zopflipng)
 $(RECOVERY_INSTALLING_TEXT_FILE): PRIVATE_RECOVERY_IMAGE_WIDTH := $(recovery_image_width)
-$(RECOVERY_INSTALLING_TEXT_FILE): PRIVATE_RECOVERY_TEXT_LIST := \
+$(RECOVERY_INSTALLING_TEXT_FILE): PRIVATE_RECOVERY_BACKGROUND_TEXT_LIST := \
   recovery_installing \
   recovery_installing_security \
   recovery_erasing \
   recovery_error \
-  recovery_no_command \
+  recovery_no_command
+$(RECOVERY_INSTALLING_TEXT_FILE): PRIVATE_RECOVERY_WIPE_DATA_TEXT_LIST := \
   recovery_cancel_wipe_data \
   recovery_factory_data_reset \
   recovery_try_again \
@@ -1608,17 +1637,17 @@
 	@rm -rf $(PRIVATE_RECOVERY_FONT_FILES_DIR)
 	@mkdir -p $(PRIVATE_RECOVERY_FONT_FILES_DIR)
 	$(foreach filename,$(PRIVATE_SOURCE_FONTS), cp $(filename) $(PRIVATE_RECOVERY_FONT_FILES_DIR) &&) true
-
 	@rm -rf $(dir $@)
 	@mkdir -p $(dir $@)
-	$(foreach text_name,$(PRIVATE_RECOVERY_TEXT_LIST), \
+	$(foreach text_name,$(PRIVATE_RECOVERY_BACKGROUND_TEXT_LIST) $(PRIVATE_RECOVERY_WIPE_DATA_TEXT_LIST), \
 	  $(eval output_file := $(dir $@)/$(patsubst recovery_%,%_text.png,$(text_name))) \
+	  $(eval center_alignment := $(if $(filter $(text_name),$(PRIVATE_RECOVERY_BACKGROUND_TEXT_LIST)), --center_alignment)) \
 	  java -jar $(PRIVATE_IMAGE_GENERATOR_JAR) \
 	    --image_width $(PRIVATE_RECOVERY_IMAGE_WIDTH) \
 	    --text_name $(text_name) \
 	    --font_dir $(PRIVATE_RECOVERY_FONT_FILES_DIR) \
 	    --resource_dir $(PRIVATE_RESOURCE_DIR) \
-	    --output_file $(output_file) && \
+	    --output_file $(output_file) $(center_alignment) && \
 	  $(PRIVATE_ZOPFLIPNG) -y --iterations=1 --filters=0 $(output_file) $(output_file) > /dev/null &&) true
 else
 RECOVERY_INSTALLING_TEXT_FILE :=
@@ -2199,7 +2228,7 @@
 $(INSTALLED_PLATFORM_ZIP) : $(SOONG_ZIP)
 # dependencies for the other partitions are defined below after their file lists
 # are known
-$(INSTALLED_PLATFORM_ZIP) : $(INTERNAL_SYSTEMIMAGE_FILES) $(pdk_classes_dex) $(pdk_odex_config_mk)
+$(INSTALLED_PLATFORM_ZIP) : $(INTERNAL_SYSTEMIMAGE_FILES) $(pdk_classes_dex) $(pdk_odex_config_mk) $(api_fingerprint)
 	$(call pretty,"Platform zip package: $(INSTALLED_PLATFORM_ZIP)")
 	rm -f $@ $@.lst
 	echo "-C $(PRODUCT_OUT)" >> $@.lst
@@ -2232,6 +2261,7 @@
 	@# Add dex-preopt files and config.
 	$(if $(PRIVATE_DEX_FILES),\
 	  echo "-C $(OUT_DIR) $(addprefix -f ,$(PRIVATE_DEX_FILES))") >> $@.lst
+	echo "-C $(dir $(api_fingerprint)) -f $(api_fingerprint)" >> $@.lst
 	touch $(PRODUCT_OUT)/pdk.mk
 	echo "-C $(PRODUCT_OUT) -f $(PRIVATE_ODEX_CONFIG) -f $(PRODUCT_OUT)/pdk.mk" >> $@.lst
 	$(SOONG_ZIP) --ignore_missing_files -o $@ @$@.lst
@@ -3253,7 +3283,9 @@
   $(HOST_LIBRARY_PATH)/libpcre2$(HOST_SHLIB_SUFFIX) \
   $(HOST_LIBRARY_PATH)/libbrotli$(HOST_SHLIB_SUFFIX) \
   $(HOST_LIBRARY_PATH)/liblp$(HOST_SHLIB_SUFFIX) \
-  $(HOST_LIBRARY_PATH)/libext4_utils$(HOST_SHLIB_SUFFIX)
+  $(HOST_LIBRARY_PATH)/libext4_utils$(HOST_SHLIB_SUFFIX) \
+  $(HOST_LIBRARY_PATH)/libfec$(HOST_SHLIB_SUFFIX) \
+  $(HOST_LIBRARY_PATH)/libsquashfs_utils$(HOST_SHLIB_SUFFIX)
 
 
 .PHONY: otatools
@@ -3394,6 +3426,8 @@
   echo "lpmake=$(notdir $(LPMAKE))" >> $(1)
   $(if $(filter true,$(PRODUCT_BUILD_SUPER_PARTITION)), $(if $(BOARD_SUPER_PARTITION_SIZE), \
     echo "build_super_partition=true" >> $(1)))
+  $(if $(filter true,$(BOARD_BUILD_RETROFIT_DYNAMIC_PARTITIONS_OTA_PACKAGE)), \
+    echo "build_retrofit_dynamic_partitions_ota_package=true" >> $(1))
   echo "super_metadata_device=$(BOARD_SUPER_PARTITION_METADATA_DEVICE)" >> $(1)
   $(if $(BOARD_SUPER_PARTITION_BLOCK_DEVICES), \
     echo "super_block_devices=$(BOARD_SUPER_PARTITION_BLOCK_DEVICES)" >> $(1))
@@ -3779,12 +3813,16 @@
 endif
 ifneq ($(BOARD_SUPER_PARTITION_GROUPS),)
 	$(hide) echo "super_partition_groups=$(BOARD_SUPER_PARTITION_GROUPS)" > $(zip_root)/META/dynamic_partitions_info.txt
+	@# Remove 'vendor' from the group partition list if the image is not available. This should only
+	@# happen to AOSP targets built without vendor.img. We can't remove the partition from the
+	@# BoardConfig file, as it's still needed elsewhere (e.g. when creating super_empty.img).
 	$(foreach group,$(BOARD_SUPER_PARTITION_GROUPS), \
+	    $(eval _group_partition_list := $(BOARD_$(call to-upper,$(group))_PARTITION_LIST)) \
+	    $(if $(INSTALLED_VENDORIMAGE_TARGET),,$(eval _group_partition_list := $(filter-out vendor,$(_group_partition_list)))) \
 	    echo "$(group)_size=$(BOARD_$(call to-upper,$(group))_SIZE)" >> $(zip_root)/META/dynamic_partitions_info.txt; \
-	    $(if $(BOARD_$(call to-upper,$(group))_PARTITION_LIST), \
-	        echo "$(group)_partition_list=$(BOARD_$(call to-upper,$(group))_PARTITION_LIST)" >> $(zip_root)/META/dynamic_partitions_info.txt;))
-endif
-
+	    $(if $(_group_partition_list), \
+	        echo "$(group)_partition_list=$(_group_partition_list)" >> $(zip_root)/META/dynamic_partitions_info.txt;))
+endif # BOARD_SUPER_PARTITION_GROUPS
 	$(hide) PATH=$(foreach p,$(INTERNAL_USERIMAGES_BINARY_PATHS),$(p):)$$PATH MKBOOTIMG=$(MKBOOTIMG) \
 	    build/make/tools/releasetools/add_img_to_target_files -a -v -p $(HOST_OUT) $(zip_root)
 	@# Zip everything up, preserving symlinks and placing META/ files first to
@@ -3850,7 +3888,7 @@
 .PHONY: otapackage
 otapackage: $(INTERNAL_OTA_PACKAGE_TARGET)
 
-ifeq ($(PRODUCT_RETROFIT_DYNAMIC_PARTITIONS),true)
+ifeq ($(BOARD_BUILD_RETROFIT_DYNAMIC_PARTITIONS_OTA_PACKAGE),true)
 name := $(TARGET_PRODUCT)
 ifeq ($(TARGET_BUILD_TYPE),debug)
   name := $(name)_debug
@@ -3876,7 +3914,7 @@
 
 otapackage otardppackage: $(INTERNAL_OTA_RETROFIT_DYNAMIC_PARTITIONS_PACKAGE_TARGET)
 
-endif # PRODUCT_RETROFIT_DYNAMIC_PARTITIONS
+endif # BOARD_BUILD_RETROFIT_DYNAMIC_PARTITIONS_OTA_PACKAGE
 
 endif    # build_ota_package
 
@@ -4096,7 +4134,7 @@
 
 systemimage: $(INSTALLED_QEMU_SYSTEMIMAGE)
 droidcore: $(INSTALLED_QEMU_SYSTEMIMAGE)
-ifeq ($(BOARD_USES_VENDORIMAGE),true)
+ifdef INSTALLED_VENDORIMAGE_TARGET
 INSTALLED_QEMU_VENDORIMAGE := $(PRODUCT_OUT)/vendor-qemu.img
 $(INSTALLED_QEMU_VENDORIMAGE): $(INSTALLED_VENDORIMAGE_TARGET) $(MK_QEMU_IMAGE_SH) $(SGDISK_HOST) $(SIMG2IMG)
 	@echo Create vendor-qemu.img
@@ -4105,7 +4143,7 @@
 vendorimage: $(INSTALLED_QEMU_VENDORIMAGE)
 droidcore: $(INSTALLED_QEMU_VENDORIMAGE)
 endif
-ifeq ($(BOARD_USES_PRODUCTIMAGE),true)
+ifdef INSTALLED_PRODUCTIMAGE_TARGET
 INSTALLED_QEMU_PRODUCTIMAGE := $(PRODUCT_OUT)/product-qemu.img
 $(INSTALLED_QEMU_PRODUCTIMAGE): $(INSTALLED_PRODUCTIMAGE_TARGET) $(MK_QEMU_IMAGE_SH) $(SGDISK_HOST) $(SIMG2IMG)
 	@echo Create product-qemu.img
@@ -4114,7 +4152,7 @@
 productimage: $(INSTALLED_QEMU_PRODUCTIMAGE)
 droidcore: $(INSTALLED_QEMU_PRODUCTIMAGE)
 endif
-ifeq ($(BOARD_USES_PRODUCT_SERVICESIMAGE),true)
+ifdef INSTALLED_PRODUCT_SERVICESIMAGE_TARGET
 INSTALLED_QEMU_PRODUCT_SERVICESIMAGE := $(PRODUCT_OUT)/product_services-qemu.img
 $(INSTALLED_QEMU_PRODUCT_SERVICESIMAGE): $(INSTALLED_PRODUCT_SERVICESIMAGE_TARGET) $(MK_QEMU_IMAGE_SH) $(SGDISK_HOST) $(SIMG2IMG)
 	@echo Create product_services-qemu.img
@@ -4123,7 +4161,7 @@
 productservicesimage: $(INSTALLED_QEMU_PRODUCT_SERVICESIMAGE)
 droidcore: $(INSTALLED_QEMU_PRODUCT_SERVICESIMAGE)
 endif
-ifeq ($(BOARD_USES_ODMIMAGE),true)
+ifdef INSTALLED_ODMIMAGE_TARGET
 INSTALLED_QEMU_ODMIMAGE := $(PRODUCT_OUT)/odm-qemu.img
 $(INSTALLED_QEMU_ODMIMAGE): $(INSTALLED_ODMIMAGE_TARGET) $(MK_QEMU_IMAGE_SH) $(SGDISK_HOST)
 	@echo Create odm-qemu.img
diff --git a/core/OWNERS b/core/OWNERS
index 570ede8..750f1fa 100644
--- a/core/OWNERS
+++ b/core/OWNERS
@@ -1 +1,3 @@
 per-file dex_preopt*.mk = ngeoffray@google.com,calin@google.com,mathewi@google.com,dbrazdil@google.com
+per-file construct_context.sh = ngeoffray@google.com,calin@google.com,mathieuc@google.com
+per-file verify_uses_libraries.sh = ngeoffray@google.com,calin@google.com,mathieuc@google.com
diff --git a/core/android_manifest.mk b/core/android_manifest.mk
index c3af942..ed759c5 100644
--- a/core/android_manifest.mk
+++ b/core/android_manifest.mk
@@ -72,8 +72,8 @@
     my_manifest_fixer_flags += --uses-non-sdk-api
 endif
 
-ifeq (true,$(LOCAL_PREFER_INTEGRITY))
-    my_manifest_fixer_flags += --prefer-integrity
+ifeq (true,$(LOCAL_PREFER_CODE_INTEGRITY))
+    my_manifest_fixer_flags += --prefer-code-integrity
 endif
 
 $(fixed_android_manifest): PRIVATE_MANIFEST_FIXER_FLAGS := $(my_manifest_fixer_flags)
diff --git a/core/clear_vars.mk b/core/clear_vars.mk
index 0fce502..b47071a 100644
--- a/core/clear_vars.mk
+++ b/core/clear_vars.mk
@@ -51,7 +51,6 @@
 LOCAL_CTS_TEST_RUNNER:=
 LOCAL_CXX:=
 LOCAL_CXX_STL := default
-LOCAL_DATA_BINDING:=
 LOCAL_DEX_PREOPT_APP_IMAGE:=
 LOCAL_DEX_PREOPT_FLAGS:=
 LOCAL_DEX_PREOPT_GENERATE_PROFILE:=
@@ -213,7 +212,7 @@
 LOCAL_PREBUILT_OBJ_FILES:=
 LOCAL_PREBUILT_STATIC_JAVA_LIBRARIES:=
 LOCAL_PREBUILT_STRIP_COMMENTS:=
-LOCAL_PREFER_INTEGRITY:=
+LOCAL_PREFER_CODE_INTEGRITY:=
 LOCAL_PRESUBMIT_DISABLED:=
 LOCAL_PRIVATE_PLATFORM_APIS:=
 LOCAL_PRIVILEGED_MODULE:=
diff --git a/core/config.mk b/core/config.mk
index 9d77fe5..c0a159d 100644
--- a/core/config.mk
+++ b/core/config.mk
@@ -569,6 +569,13 @@
 endif
 .KATI_READONLY := ALLOW_MISSING_DEPENDENCIES
 
+TARGET_BUILD_APPS_USE_PREBUILT_SDK :=
+ifdef TARGET_BUILD_APPS
+  ifndef UNBUNDLED_BUILD_SDKS_FROM_SOURCE
+    TARGET_BUILD_APPS_USE_PREBUILT_SDK := true
+  endif
+endif
+
 prebuilt_sdk_tools := prebuilts/sdk/tools
 prebuilt_sdk_tools_bin := $(prebuilt_sdk_tools)/$(HOST_OS)/bin
 
@@ -680,7 +687,7 @@
 else
 AVBTOOL := $(BOARD_CUSTOM_AVBTOOL)
 endif
-APICHECK := $(HOST_OUT_EXECUTABLES)/apicheck$(HOST_EXECUTABLE_SUFFIX)
+APICHECK := $(HOST_OUT_JAVA_LIBRARIES)/metalava$(COMMON_JAVA_PACKAGE_SUFFIX)
 FS_GET_STATS := $(HOST_OUT_EXECUTABLES)/fs_get_stats$(HOST_EXECUTABLE_SUFFIX)
 MAKE_EXT4FS := $(HOST_OUT_EXECUTABLES)/mke2fs$(HOST_EXECUTABLE_SUFFIX)
 MKEXTUSERIMG := $(HOST_OUT_EXECUTABLES)/mkuserimg_mke2fs
@@ -748,13 +755,7 @@
 MD5SUM:=md5sum
 endif
 
-APICHECK_CLASSPATH_ENTRIES := \
-    $(HOST_OUT_JAVA_LIBRARIES)/apicheck$(COMMON_JAVA_PACKAGE_SUFFIX) \
-    $(HOST_JDK_TOOLS_JAR) \
-    )
-APICHECK_CLASSPATH := $(subst $(space),:,$(strip $(APICHECK_CLASSPATH_ENTRIES)))
-
-APICHECK_COMMAND := $(APICHECK) -JXmx1024m -J"classpath $(APICHECK_CLASSPATH)"
+APICHECK_COMMAND := $(JAVA) -Xmx4g -jar $(APICHECK) --no-banner --compatible-output=yes
 
 # Boolean variable determining if the whitelist for compatible properties is enabled
 PRODUCT_COMPATIBLE_PROPERTY := false
@@ -1057,31 +1058,52 @@
 # The metadata device must be supplied to init via the kernel command-line.
 BOARD_KERNEL_CMDLINE += androidboot.super_partition=$(BOARD_SUPER_PARTITION_METADATA_DEVICE)
 
-else # PRODUCT_RETROFIT_DYNAMIC_PARTITIONS
+BOARD_BUILD_RETROFIT_DYNAMIC_PARTITIONS_OTA_PACKAGE := true
 
-# These should not be specified on devices launching with dynamic partition support.
-ifdef BOARD_SUPER_PARTITION_BLOCK_DEVICES
-$(error BOARD_SUPER_PARTITION_BLOCK_DEVICES can only be used if PRODUCT_RETROFIT_DYNAMIC_PARTITIONS is true.)
-endif
-ifdef BOARD_SUPER_PARTITION_METADATA_DEVICE
-$(error BOARD_SUPER_PARTITION_METADATA_DEVICE can only be used if PRODUCT_RETROFIT_DYNAMIC_PARTITIONS is true.)
-endif
+# If "vendor" is listed as one of the dynamic partitions but without its image available (e.g. an
+# AOSP target built without vendor image), don't build the retrofit full OTA package. Because we
+# won't be able to build meaningful super_* images for retrofitting purpose.
+ifneq (,$(filter vendor,$(BOARD_SUPER_PARTITION_PARTITION_LIST)))
+ifndef BOARD_VENDORIMAGE_FILE_SYSTEM_TYPE
+ifndef BOARD_PREBUILT_VENDORIMAGE
+BOARD_BUILD_RETROFIT_DYNAMIC_PARTITIONS_OTA_PACKAGE :=
+endif # BOARD_PREBUILT_VENDORIMAGE
+endif # BOARD_VENDORIMAGE_FILE_SYSTEM_TYPE
+endif # BOARD_SUPER_PARTITION_PARTITION_LIST
+
+else # PRODUCT_RETROFIT_DYNAMIC_PARTITIONS
 
 # For normal devices, we populate BOARD_SUPER_PARTITION_BLOCK_DEVICES so the
 # build can handle both cases consistently.
-BOARD_SUPER_PARTITION_BLOCK_DEVICES := super
+ifeq ($(BOARD_SUPER_PARTITION_METADATA_DEVICE),)
 BOARD_SUPER_PARTITION_METADATA_DEVICE := super
-BOARD_SUPER_PARTITION_SUPER_DEVICE_SIZE := $(BOARD_SUPER_PARTITION_SIZE)
+endif
+
+ifeq ($(BOARD_SUPER_PARTITION_BLOCK_DEVICES),)
+BOARD_SUPER_PARTITION_BLOCK_DEVICES := $(BOARD_SUPER_PARTITION_METADATA_DEVICE)
+endif
+
+# If only one super block device, default to super partition size.
+ifeq ($(word 2,$(BOARD_SUPER_PARTITION_BLOCK_DEVICES)),)
+BOARD_SUPER_PARTITION_$(call to-upper,$(strip $(BOARD_SUPER_PARTITION_BLOCK_DEVICES)))_DEVICE_SIZE ?= \
+    $(BOARD_SUPER_PARTITION_SIZE)
+endif
+
+ifneq ($(BOARD_SUPER_PARTITION_METADATA_DEVICE),super)
+BOARD_KERNEL_CMDLINE += androidboot.super_partition=$(BOARD_SUPER_PARTITION_METADATA_DEVICE)
+endif
+BOARD_BUILD_RETROFIT_DYNAMIC_PARTITIONS_OTA_PACKAGE :=
 
 endif # PRODUCT_RETROFIT_DYNAMIC_PARTITIONS
 endif # BOARD_SUPER_PARTITION_SIZE
 .KATI_READONLY := BOARD_SUPER_PARTITION_BLOCK_DEVICES
 .KATI_READONLY := BOARD_SUPER_PARTITION_METADATA_DEVICE
+.KATI_READONLY := BOARD_BUILD_RETROFIT_DYNAMIC_PARTITIONS_OTA_PACKAGE
 
 $(foreach device,$(call to-upper,$(BOARD_SUPER_PARTITION_BLOCK_DEVICES)), \
     $(eval BOARD_SUPER_PARTITION_$(device)_DEVICE_SIZE := $(strip $(BOARD_SUPER_PARTITION_$(device)_DEVICE_SIZE))) \
     $(if $(BOARD_SUPER_PARTITION_$(device)_DEVICE_SIZE),, \
-        $(error $(BOARD_SUPER_PARTITION_$(device)_DEVICE_SIZE must not be empty))) \
+        $(error BOARD_SUPER_PARTITION_$(device)_DEVICE_SIZE must not be empty)) \
     $(eval .KATI_READONLY := BOARD_SUPER_PARTITION_$(device)_DEVICE_SIZE))
 
 endif # PRODUCT_BUILD_SUPER_PARTITION
diff --git a/core/config_sanitizers.mk b/core/config_sanitizers.mk
index 51b859e..6c9caa8 100644
--- a/core/config_sanitizers.mk
+++ b/core/config_sanitizers.mk
@@ -337,7 +337,7 @@
       my_ldflags += -Wl,--as-needed
     endif
 
-    ifeq ($(LOCAL_MODULE_CLASS),EXECUTABLES)
+    ifneq ($(filter EXECUTABLES NATIVE_TESTS,$(LOCAL_MODULE_CLASS)),)
       ifneq ($(LOCAL_FORCE_STATIC_EXECUTABLE),true)
         my_linker := $($(LOCAL_2ND_ARCH_VAR_PREFIX)ADDRESS_SANITIZER_LINKER)
         # Make sure linker_asan get installed.
diff --git a/core/definitions.mk b/core/definitions.mk
index 50c26d3..a675080 100644
--- a/core/definitions.mk
+++ b/core/definitions.mk
@@ -2370,7 +2370,7 @@
 define run-appcompat
 $(hide) \
   echo "appcompat.sh output:" >> $(PRODUCT_OUT)/appcompat/$(PRIVATE_MODULE).log && \
-  PACKAGING=$(TARGET_OUT_COMMON_INTERMEDIATES)/PACKAGING art/tools/veridex/appcompat.sh --dex-file=$@ 2>&1 >> $(PRODUCT_OUT)/appcompat/$(PRIVATE_MODULE).log
+  PACKAGING=$(TARGET_OUT_COMMON_INTERMEDIATES)/PACKAGING ANDROID_LOG_TAGS="*:e" art/tools/veridex/appcompat.sh --dex-file=$@ 2>&1 >> $(PRODUCT_OUT)/appcompat/$(PRIVATE_MODULE).log
 endef
 appcompat-files = \
   art/tools/veridex/appcompat.sh \
@@ -2704,9 +2704,9 @@
 $(INTERNAL_PLATFORM_HIDDENAPI_FLAGS): $(2)
 $(INTERNAL_PLATFORM_HIDDENAPI_FLAGS): PRIVATE_FLAGS_INPUTS := $$(PRIVATE_FLAGS_INPUTS) $(2)
 
-$(INTERNAL_PLATFORM_HIDDENAPI_GREYLIST_METADATA): $(5)
+$(INTERNAL_PLATFORM_HIDDENAPI_GREYLIST_METADATA): $(3)
 $(INTERNAL_PLATFORM_HIDDENAPI_GREYLIST_METADATA): \
-    PRIVATE_METADATA_INPUTS := $$(PRIVATE_METADATA_INPUTS) $(5)
+    PRIVATE_METADATA_INPUTS := $$(PRIVATE_METADATA_INPUTS) $(3)
 
 endif
 endef
@@ -2904,7 +2904,7 @@
 define check-api
 $(TARGET_OUT_COMMON_INTERMEDIATES)/PACKAGING/$(strip $(1))-timestamp: $(2) $(3) $(4) $(APICHECK) $(9)
 	@echo "Checking API:" $(1)
-	$(hide) ( $(APICHECK_COMMAND) $(6) $(2) $(3) $(4) $(5) || ( $(7) ; exit 38 ) )
+	$(hide) ( $(APICHECK_COMMAND) --check-api-files $(6) $(2) $(3) $(4) $(5) || ( $(7) ; exit 38 ) )
 	$(hide) mkdir -p $$(dir $$@)
 	$(hide) touch $$@
 $(8): $(TARGET_OUT_COMMON_INTERMEDIATES)/PACKAGING/$(strip $(1))-timestamp
diff --git a/core/dex_preopt_libart_boot.mk b/core/dex_preopt_libart_boot.mk
index 156ce02..b31f5a8 100644
--- a/core/dex_preopt_libart_boot.mk
+++ b/core/dex_preopt_libart_boot.mk
@@ -90,11 +90,13 @@
 	@echo "target dex2oat: $@"
 	@mkdir -p $(dir $@)
 	@mkdir -p $(dir $($(PRIVATE_2ND_ARCH_VAR_PREFIX)LIBART_TARGET_BOOT_OAT_UNSTRIPPED))
-	@rm -f $(dir $@)/*.art $(dir $@)/*.oat
+	@rm -f $(dir $@)/*.art $(dir $@)/*.oat $(dir $@)/*.invocation
 	@rm -f $(dir $($(PRIVATE_2ND_ARCH_VAR_PREFIX)LIBART_TARGET_BOOT_OAT_UNSTRIPPED))/*.art
 	@rm -f $(dir $($(PRIVATE_2ND_ARCH_VAR_PREFIX)LIBART_TARGET_BOOT_OAT_UNSTRIPPED))/*.oat
+	@rm -f $(dir $($(PRIVATE_2ND_ARCH_VAR_PREFIX)LIBART_TARGET_BOOT_OAT_UNSTRIPPED))/*.invocation
 	$(hide) $(DEX2OAT_BOOT_IMAGE_LOG_TAGS) $(DEX2OAT) --runtime-arg -Xms$(DEX2OAT_IMAGE_XMS) \
 		--avoid-storing-invocation \
+		--write-invocation-to=$(patsubst %.art,%.invocation,$@) \
 		--runtime-arg -Xmx$(DEX2OAT_IMAGE_XMX) \
 		$(PRIVATE_BOOT_IMAGE_FLAGS) \
 		$(addprefix --dex-file=,$(LIBART_TARGET_BOOT_DEX_FILES)) \
diff --git a/core/dex_preopt_odex_install.mk b/core/dex_preopt_odex_install.mk
index 9f29c68..17eeb8a 100644
--- a/core/dex_preopt_odex_install.mk
+++ b/core/dex_preopt_odex_install.mk
@@ -3,7 +3,7 @@
 # Output variables: LOCAL_DEX_PREOPT, LOCAL_UNCOMPRESS_DEX, built_odex,
 #                   dexpreopt_boot_jar_module
 
-ifeq (true,$(LOCAL_PREFER_INTEGRITY))
+ifeq (true,$(LOCAL_PREFER_CODE_INTEGRITY))
   LOCAL_UNCOMPRESS_DEX := true
 else
   LOCAL_UNCOMPRESS_DEX :=
@@ -181,7 +181,7 @@
   $(call add_json_str,  BuildPath,                     $(LOCAL_BUILT_MODULE))
   $(call add_json_str,  DexPath,                       $$1)
   $(call add_json_str,  ExtrasOutputPath,              $$2)
-  $(call add_json_bool, PreferIntegrity,               $(filter true,$(LOCAL_PREFER_INTEGRITY)))
+  $(call add_json_bool, PreferCodeIntegrity,           $(filter true,$(LOCAL_PREFER_CODE_INTEGRITY)))
   $(call add_json_bool, Privileged,                    $(filter true,$(LOCAL_PRIVILEGED_MODULE)))
   $(call add_json_bool, UncompressedDex,               $(filter true,$(LOCAL_UNCOMPRESS_DEX)))
   $(call add_json_bool, HasApkLibraries,               $(LOCAL_APK_LIBRARIES))
@@ -253,7 +253,13 @@
     LOCAL_POST_INSTALL_CMD += &&
   endif
 
-  LOCAL_POST_INSTALL_CMD += for i in $$(zipinfo -1 $(my_dexpreopt_zip)); do mkdir -p $(PRODUCT_OUT)/$$(dirname $$i); done && unzip -qo -d $(PRODUCT_OUT) $(my_dexpreopt_zip)
+  LOCAL_POST_INSTALL_CMD += \
+    for i in $$(zipinfo -1 $(my_dexpreopt_zip)); \
+      do mkdir -p $(PRODUCT_OUT)/$$(dirname $$i); \
+    done && \
+    ( unzip -qo -d $(PRODUCT_OUT) $(my_dexpreopt_zip) 2>&1 | grep -v "zipfile is empty"; exit $${PIPESTATUS[0]} ) || \
+      ( code=$$?; if [ $$code -ne 0 -a $$code -ne 1 ]; then exit $$code; fi )
+
   $(LOCAL_INSTALLED_MODULE): PRIVATE_POST_INSTALL_CMD := $(LOCAL_POST_INSTALL_CMD)
   $(LOCAL_INSTALLED_MODULE): $(my_dexpreopt_zip)
 
diff --git a/core/java.mk b/core/java.mk
index 932a421..e564db2 100644
--- a/core/java.mk
+++ b/core/java.mk
@@ -109,7 +109,7 @@
 
 aidl_preprocess_import :=
 ifdef LOCAL_SDK_VERSION
-ifneq ($(filter current system_current test_current core_current, $(LOCAL_SDK_VERSION)$(TARGET_BUILD_APPS)),)
+ifneq ($(filter current system_current test_current core_current, $(LOCAL_SDK_VERSION)$(TARGET_BUILD_APPS_USE_PREBUILT_SDK)),)
   # LOCAL_SDK_VERSION is current and no TARGET_BUILD_APPS
   aidl_preprocess_import := $(TARGET_OUT_COMMON_INTERMEDIATES)/framework.aidl
 else
diff --git a/core/java_common.mk b/core/java_common.mk
index f4c47c8..ac26e5e 100644
--- a/core/java_common.mk
+++ b/core/java_common.mk
@@ -29,7 +29,7 @@
     LOCAL_JAVA_LANGUAGE_VERSION := 1.7
   else ifneq (,$(filter $(LOCAL_SDK_VERSION), $(TARGET_SDK_VERSIONS_WITHOUT_JAVA_19_SUPPORT)))
     LOCAL_JAVA_LANGUAGE_VERSION := 1.8
-  else ifneq (,$(LOCAL_SDK_VERSION)$(TARGET_BUILD_APPS))
+  else ifneq (,$(LOCAL_SDK_VERSION)$(TARGET_BUILD_APPS_USE_PREBUILT_SDK))
     # TODO(ccross): allow 1.9 for current and unbundled once we have SDK system modules
     LOCAL_JAVA_LANGUAGE_VERSION := 1.8
   else
@@ -276,7 +276,7 @@
       my_system_modules := $(DEFAULT_SYSTEM_MODULES)
     endif  # LOCAL_NO_STANDARD_LIBRARIES
 
-    ifneq (,$(TARGET_BUILD_APPS))
+    ifneq (,$(TARGET_BUILD_APPS_USE_PREBUILT_SDK))
       sdk_libs := $(foreach lib_name,$(LOCAL_SDK_LIBRARIES),$(call resolve-prebuilt-sdk-module,system_current,$(lib_name)))
     else
       # When SDK libraries are referenced from modules built without SDK, provide the all APIs to them
@@ -291,7 +291,7 @@
              Choices are: $(TARGET_AVAILABLE_SDK_VERSIONS))
     endif
 
-    ifneq (,$(TARGET_BUILD_APPS)$(filter-out %current,$(LOCAL_SDK_VERSION)))
+    ifneq (,$(TARGET_BUILD_APPS_USE_PREBUILT_SDK)$(filter-out %current,$(LOCAL_SDK_VERSION)))
       # TARGET_BUILD_APPS mode or numbered SDK. Use prebuilt modules.
       sdk_module := $(call resolve-prebuilt-sdk-module,$(LOCAL_SDK_VERSION))
       sdk_libs := $(foreach lib_name,$(LOCAL_SDK_LIBRARIES),$(call resolve-prebuilt-sdk-module,$(LOCAL_SDK_VERSION),$(lib_name)))
@@ -333,7 +333,7 @@
   # related classes to be present. This change adds stubs needed for
   # javac to compile lambdas.
   ifneq ($(LOCAL_NO_STANDARD_LIBRARIES),true)
-    ifdef TARGET_BUILD_APPS
+    ifdef TARGET_BUILD_APPS_USE_PREBUILT_SDK
       full_java_bootclasspath_libs += $(call java-lib-header-files,sdk-core-lambda-stubs)
     else
       full_java_bootclasspath_libs += $(call java-lib-header-files,core-lambda-stubs)
diff --git a/core/java_renderscript.mk b/core/java_renderscript.mk
index 406d679..13a6f8e 100644
--- a/core/java_renderscript.mk
+++ b/core/java_renderscript.mk
@@ -82,8 +82,8 @@
 $(rs_generated_src_jar): $(renderscript_sources_fullpath) $(LOCAL_RENDERSCRIPT_CC) $(SOONG_ZIP)
 	$(transform-renderscripts-to-java-and-bc)
 
-# include the dependency files (.d/.P) generated by llvm-rs-cc.
-$(call include-depfile,$(rs_generated_src_jar).P,$(rs_generated_src_jar))
+# include the dependency files (.d) generated by llvm-rs-cc.
+$(call include-depfile,$(rs_generated_src_jar).d,$(rs_generated_src_jar))
 
 ifneq ($(LOCAL_RENDERSCRIPT_COMPATIBILITY),)
 
diff --git a/core/package_internal.mk b/core/package_internal.mk
index 451fce7..6987842 100644
--- a/core/package_internal.mk
+++ b/core/package_internal.mk
@@ -309,23 +309,6 @@
 
 rs_compatibility_jni_libs :=
 
-ifeq ($(LOCAL_DATA_BINDING),true)
-data_binding_intermediates := $(intermediates.COMMON)/data-binding
-
-LOCAL_JAVACFLAGS += -processorpath $(DATA_BINDING_COMPILER) -s $(data_binding_intermediates)/anno-src
-
-LOCAL_STATIC_JAVA_LIBRARIES += databinding-baselibrary
-LOCAL_STATIC_JAVA_AAR_LIBRARIES += databinding-library databinding-adapters
-
-data_binding_res_in := $(LOCAL_RESOURCE_DIR)
-data_binding_res_out := $(data_binding_intermediates)/res
-
-# Replace with the processed merged res dir.
-LOCAL_RESOURCE_DIR := $(data_binding_res_out)
-
-LOCAL_AAPT_FLAGS += --auto-add-overlay --extra-packages com.android.databinding.library
-endif  # LOCAL_DATA_BINDING
-
 # If the module is a compressed module, we don't pre-opt it because its final
 # installation location will be the data partition.
 ifdef LOCAL_COMPRESSED_MODULE
@@ -460,34 +443,6 @@
 $(LOCAL_INTERMEDIATE_TARGETS): \
     PRIVATE_ANDROID_MANIFEST := $(full_android_manifest)
 
-ifeq ($(LOCAL_DATA_BINDING),true)
-data_binding_stamp := $(data_binding_intermediates)/data-binding.stamp
-$(data_binding_stamp): PRIVATE_INTERMEDIATES := $(data_binding_intermediates)
-$(data_binding_stamp): PRIVATE_MANIFEST := $(full_android_manifest)
-# Generate code into $(LOCAL_INTERMEDIATE_SOURCE_DIR) so that the generated .java files
-# will be automatically picked up by function compile-java.
-$(data_binding_stamp): PRIVATE_SRC_OUT := $(LOCAL_INTERMEDIATE_SOURCE_DIR)/data-binding
-$(data_binding_stamp): PRIVATE_XML_OUT := $(data_binding_intermediates)/xml
-$(data_binding_stamp): PRIVATE_RES_OUT := $(data_binding_res_out)
-$(data_binding_stamp): PRIVATE_RES_IN := $(data_binding_res_in)
-$(data_binding_stamp): PRIVATE_ANNO_SRC_DIR := $(data_binding_intermediates)/anno-src
-
-$(data_binding_stamp) : $(all_res_assets) $(full_android_manifest) \
-    $(DATA_BINDING_COMPILER)
-	@echo "Data-binding process: $@"
-	@rm -rf $(PRIVATE_INTERMEDIATES) $(PRIVATE_SRC_OUT) && \
-	  mkdir -p $(PRIVATE_INTERMEDIATES) $(PRIVATE_SRC_OUT) \
-	      $(PRIVATE_XML_OUT) $(PRIVATE_RES_OUT) $(PRIVATE_ANNO_SRC_DIR)
-	$(hide) $(JAVA) -classpath $(DATA_BINDING_COMPILER) android.databinding.tool.MakeCopy \
-	  $(PRIVATE_MANIFEST) $(PRIVATE_SRC_OUT) $(PRIVATE_XML_OUT) $(PRIVATE_RES_OUT) $(PRIVATE_RES_IN)
-	$(hide) touch $@
-
-# Make sure the data-binding process happens before javac and generation of R.java.
-$(R_file_stamp): $(data_binding_stamp)
-$(java_source_list_file): $(data_binding_stamp)
-$(full_classes_compiled_jar): $(data_binding_stamp)
-endif  # LOCAL_DATA_BINDING
-
 framework_res_package_export :=
 
 ifneq ($(LOCAL_NO_STANDARD_LIBRARIES),true)
@@ -496,7 +451,7 @@
 # resources.
 ifeq ($(LOCAL_SDK_RES_VERSION),core_current)
 # core_current doesn't contain any framework resources.
-else ifneq ($(filter-out current system_current test_current,$(LOCAL_SDK_RES_VERSION))$(if $(TARGET_BUILD_APPS),$(filter current system_current test_current,$(LOCAL_SDK_RES_VERSION))),)
+else ifneq ($(filter-out current system_current test_current,$(LOCAL_SDK_RES_VERSION))$(if $(TARGET_BUILD_APPS_USE_PREBUILT_SDK),$(filter current system_current test_current,$(LOCAL_SDK_RES_VERSION))),)
 # for released sdk versions, the platform resources were built into android.jar.
 framework_res_package_export := \
     $(call resolve-prebuilt-sdk-jar-path,$(LOCAL_SDK_RES_VERSION))
@@ -678,8 +633,8 @@
 	@# Keep a copy of apk with classes.dex unstripped
 	$(hide) cp -f $@ $(dir $@)package.dex.apk
 endif  # BUILD_PLATFORM_ZIP
-	$(PRIVATE_STRIP_SCRIPT) $@ $@.tmp
-	mv -f $@.tmp $@
+	mv -f $@ $@.tmp
+	$(PRIVATE_STRIP_SCRIPT) $@.tmp $@
 endif  # LOCAL_DEX_PREOPT
 	$(sign-package)
 ifdef LOCAL_COMPRESSED_MODULE
diff --git a/core/prebuilt_internal.mk b/core/prebuilt_internal.mk
index 013497f..66913c1 100644
--- a/core/prebuilt_internal.mk
+++ b/core/prebuilt_internal.mk
@@ -357,12 +357,14 @@
 ifneq ($(BUILD_PLATFORM_ZIP),)
 $(built_module) : .KATI_IMPLICIT_OUTPUTS := $(dir $(LOCAL_BUILT_MODULE))package.dex.apk
 endif
+ifneq ($(LOCAL_CERTIFICATE),PRESIGNED)
 ifdef LOCAL_DEX_PREOPT
 $(built_module) : PRIVATE_STRIP_SCRIPT := $(intermediates)/strip.sh
 $(built_module) : $(intermediates)/strip.sh
 $(built_module) : | $(DEXPREOPT_GEN_DEPS)
 $(built_module) : .KATI_DEPFILE := $(built_module).d
 endif
+endif
 $(built_module) : $(my_prebuilt_src_file) | $(ZIPALIGN) $(ZIP2ZIP) $(SIGNAPK_JAR)
 	$(transform-prebuilt-to-target)
 	$(uncompress-prebuilt-embedded-jni-libs)
@@ -387,8 +389,8 @@
 	$(run-appcompat)
 endif  # module_run_appcompat
 ifdef LOCAL_DEX_PREOPT
-	$(PRIVATE_STRIP_SCRIPT) $@ $@.tmp
-	mv -f $@.tmp $@
+	mv -f $@ $@.tmp
+	$(PRIVATE_STRIP_SCRIPT) $@.tmp $@
 endif  # LOCAL_DEX_PREOPT
 	$(sign-package)
 	# No need for align-package because sign-package takes care of alignment
diff --git a/core/product_config.mk b/core/product_config.mk
index ac7fe91..f0f7da1 100644
--- a/core/product_config.mk
+++ b/core/product_config.mk
@@ -175,15 +175,9 @@
 include $(BUILD_SYSTEM)/product.mk
 include $(BUILD_SYSTEM)/device.mk
 
-ifneq ($(strip $(TARGET_BUILD_APPS)),)
-# An unbundled app build needs only the core product makefiles.
-all_product_configs := $(call get-product-makefiles,\
-    $(SRC_TARGET_DIR)/product/AndroidProducts.mk)
-else
 # Read in all of the product definitions specified by the AndroidProducts.mk
 # files in the tree.
 all_product_configs := $(get-all-product-makefiles)
-endif
 
 all_named_products :=
 
diff --git a/core/soong_config.mk b/core/soong_config.mk
index 3dc6d9a..85be1e7 100644
--- a/core/soong_config.mk
+++ b/core/soong_config.mk
@@ -36,6 +36,7 @@
 
 $(call add_json_bool, Allow_missing_dependencies,        $(ALLOW_MISSING_DEPENDENCIES))
 $(call add_json_bool, Unbundled_build,                   $(TARGET_BUILD_APPS))
+$(call add_json_bool, Unbundled_build_sdks_from_source,  $(UNBUNDLED_BUILD_SDKS_FROM_SOURCE))
 $(call add_json_bool, Pdk,                               $(filter true,$(TARGET_BUILD_PDK)))
 
 $(call add_json_bool, Debuggable,                        $(filter userdebug eng,$(TARGET_BUILD_VARIANT)))
diff --git a/core/static_java_library.mk b/core/static_java_library.mk
index 2a87705..cee7c9e 100644
--- a/core/static_java_library.mk
+++ b/core/static_java_library.mk
@@ -110,7 +110,7 @@
 framework_res_package_export :=
 # Please refer to package.mk
 ifneq ($(LOCAL_NO_STANDARD_LIBRARIES),true)
-ifneq ($(filter-out current system_current test_current,$(LOCAL_SDK_RES_VERSION))$(if $(TARGET_BUILD_APPS),$(filter current system_current test_current,$(LOCAL_SDK_RES_VERSION))),)
+ifneq ($(filter-out current system_current test_current,$(LOCAL_SDK_RES_VERSION))$(if $(TARGET_BUILD_APPS_USE_PREBUILT_SDK),$(filter current system_current test_current,$(LOCAL_SDK_RES_VERSION))),)
 framework_res_package_export := \
     $(call resolve-prebuilt-sdk-jar-path,$(LOCAL_SDK_RES_VERSION))
 else
diff --git a/envsetup.sh b/envsetup.sh
index 561083d..62a64b6 100644
--- a/envsetup.sh
+++ b/envsetup.sh
@@ -266,7 +266,14 @@
     fi
 
     export PATH=$ANDROID_BUILD_PATHS$PATH
-    export PYTHONPATH=$T/development/python-packages:$PYTHONPATH
+
+    # out with the duplicate old
+    if [ -n $ANDROID_PYTHONPATH ]; then
+        export PYTHONPATH=${PYTHONPATH//$ANDROID_PYTHONPATH/}
+    fi
+    # and in with the new
+    export ANDROID_PYTHONPATH=$T/development/python-packages:
+    export PYTHONPATH=$ANDROID_PYTHONPATH$PYTHONPATH
 
     export ANDROID_JAVA_HOME=$(get_abs_build_var ANDROID_JAVA_HOME)
     export JAVA_HOME=$ANDROID_JAVA_HOME
@@ -765,6 +772,9 @@
 {
     local TOPFILE=build/make/core/envsetup.mk
     local HERE=$PWD
+    if [ "$1" ]; then
+        \cd $1
+    fi;
     local T=
     while [ \( ! \( -f $TOPFILE \) \) -a \( $PWD != "/" \) ]; do
         T=`PWD= /bin/pwd`
@@ -845,24 +855,29 @@
             # Remove the leading ./ and trailing / if any exists.
             DIR=${DIR#./}
             DIR=${DIR%/}
-            if [ -f $DIR/Android.mk -o -f $DIR/Android.bp ]; then
-                local TO_CHOP=`(\cd -P -- $T && pwd -P) | wc -c | tr -d ' '`
-                local TO_CHOP=`expr $TO_CHOP + 1`
-                local START=`PWD= /bin/pwd`
-                local MDIR=`echo $START | cut -c${TO_CHOP}-`
-                if [ "$MDIR" = "" ] ; then
-                    MDIR=$DIR
-                else
-                    MDIR=$MDIR/$DIR
+            local M
+            if [ "$DIR_MODULES" = "" ]; then
+                M=$(findmakefile $DIR)
+            else
+                # Only check the target directory if a module is specified.
+                if [ -f $DIR/Android.mk -o -f $DIR/Android.bp ]; then
+                    local HERE=$PWD
+                    cd $DIR
+                    M=`PWD= /bin/pwd`
+                    M=$M/Android.mk
+                    cd $HERE
                 fi
-                MDIR=${MDIR%/.}
+            fi
+            if [ "$M" ]; then
+                # Remove the path to top as the makefilepath needs to be relative
+                local M=`echo $M|sed 's:'$T'/::'`
                 if [ "$DIR_MODULES" = "" ]; then
-                    MODULES_IN_PATHS="$MODULES_IN_PATHS MODULES-IN-$MDIR"
-                    GET_INSTALL_PATHS="$GET_INSTALL_PATHS GET-INSTALL-PATH-IN-$MDIR"
+                    MODULES_IN_PATHS="$MODULES_IN_PATHS MODULES-IN-$(dirname ${M})"
+                    GET_INSTALL_PATHS="$GET_INSTALL_PATHS GET-INSTALL-PATH-IN-$(dirname ${M})"
                 else
                     MODULES="$MODULES $DIR_MODULES"
                 fi
-                MAKEFILE="$MAKEFILE $MDIR/Android.mk"
+                MAKEFILE="$MAKEFILE $M"
             else
                 case $DIR in
                   showcommands | snod | dist | *=*) ARGS="$ARGS $DIR";;
diff --git a/target/Android.mk b/target/Android.mk
deleted file mode 100644
index 9929b00..0000000
--- a/target/Android.mk
+++ /dev/null
@@ -1,23 +0,0 @@
-#
-# Copyright (C) 2017 The Android Open Source Project
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#      http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-#
-
-LOCAL_PATH := $(call my-dir)
-
-# Only if this Android.mk was included not by a symlink should it be used.
-# This facilitates the transition away from symlinks: b/64397960
-ifeq ($(LOCAL_PATH),build/make/target)
-include $(call first-makefiles-under,$(LOCAL_PATH))
-endif
diff --git a/target/board/BoardConfigEmuCommon.mk b/target/board/BoardConfigEmuCommon.mk
index 38f79fd..55cd546 100644
--- a/target/board/BoardConfigEmuCommon.mk
+++ b/target/board/BoardConfigEmuCommon.mk
@@ -20,8 +20,6 @@
 # the GLES renderer disables itself if host GL acceleration isn't available.
 USE_OPENGL_RENDERER := true
 
-TARGET_COPY_OUT_VENDOR := vendor
-
 # ~100 MB vendor image. Please adjust system image / vendor image sizes
 # when finalizing them. The partition size needs to be a multiple of image
 # block size: 4096.
diff --git a/target/board/BoardConfigGsiCommon.mk b/target/board/BoardConfigGsiCommon.mk
index 73af020..a853b3c 100644
--- a/target/board/BoardConfigGsiCommon.mk
+++ b/target/board/BoardConfigGsiCommon.mk
@@ -6,6 +6,9 @@
 
 include build/make/target/board/BoardConfigMainlineCommon.mk
 
+# Enable system property split for Treble
+BOARD_PROPERTY_OVERRIDES_SPLIT_ENABLED := true
+
 # This flag is set by mainline but isn't desired for GSI.
 BOARD_USES_SYSTEM_OTHER_ODEX :=
 
@@ -14,9 +17,17 @@
 # we explicit specify this need below (even though it's the current default).
 TARGET_USERIMAGES_SPARSE_EXT_DISABLED := false
 
+# system.img is always ext4 with sparse option
+# GSI also includes make_f2fs to support userdata parition in f2fs
+# for some devices
+TARGET_USERIMAGES_USE_F2FS := true
+
 # Enable dynamic system image size and reserved 64MB in it.
 BOARD_SYSTEMIMAGE_PARTITION_RESERVED_SIZE := 67108864
 
+# Generic AOSP image always requires separate vendor.img
+TARGET_COPY_OUT_VENDOR := vendor
+
 # Android Verified Boot (AVB):
 #   Set AVB_VBMETA_IMAGE_FLAGS_VERIFICATION_DISABLED (--flag 2) in
 #   vbmeta.img to disable AVB verification.
diff --git a/target/board/generic_arm64_a/BoardConfig.mk b/target/board/generic_arm64_a/BoardConfig.mk
index 34a8ac0..f77dbe5 100644
--- a/target/board/generic_arm64_a/BoardConfig.mk
+++ b/target/board/generic_arm64_a/BoardConfig.mk
@@ -14,7 +14,7 @@
 # limitations under the License.
 #
 
-include build/make/target/board/treble_common_64.mk
+include build/make/target/board/BoardConfigGsiCommon.mk
 
 TARGET_ARCH := arm64
 TARGET_ARCH_VARIANT := armv8-a
diff --git a/target/board/generic_arm64_ab/BoardConfig.mk b/target/board/generic_arm64_ab/BoardConfig.mk
index 88b90a8..073eccb 100644
--- a/target/board/generic_arm64_ab/BoardConfig.mk
+++ b/target/board/generic_arm64_ab/BoardConfig.mk
@@ -14,7 +14,7 @@
 # limitations under the License.
 #
 
-include build/make/target/board/treble_common_64.mk
+include build/make/target/board/BoardConfigGsiCommon.mk
 
 TARGET_ARCH := arm64
 TARGET_ARCH_VARIANT := armv8-a
@@ -28,7 +28,7 @@
 TARGET_2ND_CPU_ABI2 := armeabi
 TARGET_2ND_CPU_VARIANT := generic
 
-# Enable A/B update
+# Enable System-as-Root
 TARGET_NO_RECOVERY := true
 BOARD_BUILD_SYSTEM_ROOT_IMAGE := true
 
diff --git a/target/board/generic_arm_a/BoardConfig.mk b/target/board/generic_arm_a/BoardConfig.mk
index 57a5196..cba222a 100644
--- a/target/board/generic_arm_a/BoardConfig.mk
+++ b/target/board/generic_arm_a/BoardConfig.mk
@@ -14,10 +14,13 @@
 # limitations under the License.
 #
 
-include build/make/target/board/treble_common_32.mk
+include build/make/target/board/BoardConfigGsiCommon.mk
 
 TARGET_ARCH := arm
 TARGET_ARCH_VARIANT := armv7-a-neon
 TARGET_CPU_ABI := armeabi-v7a
 TARGET_CPU_ABI2 := armeabi
 TARGET_CPU_VARIANT := generic
+
+# Legacy GSI keeps 32 bits binder for 32 bits CPU Arch
+TARGET_USES_64_BIT_BINDER := false
diff --git a/target/board/generic_arm_ab/BoardConfig.mk b/target/board/generic_arm_ab/BoardConfig.mk
index 3d14842..087543e 100644
--- a/target/board/generic_arm_ab/BoardConfig.mk
+++ b/target/board/generic_arm_ab/BoardConfig.mk
@@ -14,7 +14,7 @@
 # limitations under the License.
 #
 
-include build/make/target/board/treble_common_32.mk
+include build/make/target/board/BoardConfigGsiCommon.mk
 
 TARGET_ARCH := arm
 TARGET_ARCH_VARIANT := armv7-a-neon
@@ -22,7 +22,10 @@
 TARGET_CPU_ABI2 := armeabi
 TARGET_CPU_VARIANT := generic
 
-# Enable A/B update
+# Legacy GSI keeps 32 bits binder for 32 bits CPU Arch
+TARGET_USES_64_BIT_BINDER := false
+
+# Enable System-as-Root
 TARGET_NO_RECOVERY := true
 BOARD_BUILD_SYSTEM_ROOT_IMAGE := true
 
diff --git a/target/board/generic_x86_64_a/BoardConfig.mk b/target/board/generic_x86_64_a/BoardConfig.mk
index 2c02604..1dd5e48 100644
--- a/target/board/generic_x86_64_a/BoardConfig.mk
+++ b/target/board/generic_x86_64_a/BoardConfig.mk
@@ -14,7 +14,7 @@
 # limitations under the License.
 #
 
-include build/make/target/board/treble_common_64.mk
+include build/make/target/board/BoardConfigGsiCommon.mk
 
 TARGET_CPU_ABI := x86_64
 TARGET_ARCH := x86_64
diff --git a/target/board/generic_x86_64_ab/BoardConfig.mk b/target/board/generic_x86_64_ab/BoardConfig.mk
index a098dfe..09ce95d 100644
--- a/target/board/generic_x86_64_ab/BoardConfig.mk
+++ b/target/board/generic_x86_64_ab/BoardConfig.mk
@@ -14,7 +14,7 @@
 # limitations under the License.
 #
 
-include build/make/target/board/treble_common_64.mk
+include build/make/target/board/BoardConfigGsiCommon.mk
 
 TARGET_CPU_ABI := x86_64
 TARGET_ARCH := x86_64
@@ -24,11 +24,11 @@
 TARGET_2ND_ARCH := x86
 TARGET_2ND_ARCH_VARIANT := x86_64
 
+# Enable System-as-Root
+TARGET_NO_RECOVERY := true
+BOARD_BUILD_SYSTEM_ROOT_IMAGE := true
+
 # Set this to create /cache mount point for non-A/B devices that mounts /cache.
 # The partition size doesn't matter, just to make build pass.
 BOARD_CACHEIMAGE_FILE_SYSTEM_TYPE := ext4
 BOARD_CACHEIMAGE_PARTITION_SIZE := 16777216
-
-# Enable A/B update
-TARGET_NO_RECOVERY := true
-BOARD_BUILD_SYSTEM_ROOT_IMAGE := true
diff --git a/target/board/generic_x86_a/BoardConfig.mk b/target/board/generic_x86_a/BoardConfig.mk
index 67cb07d..53acffd 100644
--- a/target/board/generic_x86_a/BoardConfig.mk
+++ b/target/board/generic_x86_a/BoardConfig.mk
@@ -14,8 +14,11 @@
 # limitations under the License.
 #
 
-include build/make/target/board/treble_common_32.mk
+include build/make/target/board/BoardConfigGsiCommon.mk
 
 TARGET_CPU_ABI := x86
 TARGET_ARCH := x86
 TARGET_ARCH_VARIANT := x86
+
+# Legacy GSI keeps 32 bits binder for 32 bits CPU Arch
+TARGET_USES_64_BIT_BINDER := false
diff --git a/target/board/generic_x86_ab/BoardConfig.mk b/target/board/generic_x86_ab/BoardConfig.mk
index db4dacd..cc8ab70 100644
--- a/target/board/generic_x86_ab/BoardConfig.mk
+++ b/target/board/generic_x86_ab/BoardConfig.mk
@@ -14,17 +14,20 @@
 # limitations under the License.
 #
 
-include build/make/target/board/treble_common_32.mk
+include build/make/target/board/BoardConfigGsiCommon.mk
 
 TARGET_CPU_ABI := x86
 TARGET_ARCH := x86
 TARGET_ARCH_VARIANT := x86
 
+# Legacy GSI keeps 32 bits binder for 32 bits CPU Arch
+TARGET_USES_64_BIT_BINDER := false
+
+# Enable System-as-Root
+TARGET_NO_RECOVERY := true
+BOARD_BUILD_SYSTEM_ROOT_IMAGE := true
+
 # Set this to create /cache mount point for non-A/B devices that mounts /cache.
 # The partition size doesn't matter, just to make build pass.
 BOARD_CACHEIMAGE_FILE_SYSTEM_TYPE := ext4
 BOARD_CACHEIMAGE_PARTITION_SIZE := 16777216
-
-# Enable A/B update
-TARGET_NO_RECOVERY := true
-BOARD_BUILD_SYSTEM_ROOT_IMAGE := true
diff --git a/target/board/treble_common.mk b/target/board/treble_common.mk
deleted file mode 100644
index eda5b37..0000000
--- a/target/board/treble_common.mk
+++ /dev/null
@@ -1,69 +0,0 @@
-#
-# Copyright (C) 2017 The Android Open-Source Project
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#      http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-#
-
-# Common boardconfig settings for generic AOSP products targetting mobile
-# (phone/table) devices.
-
-# VNDK
-BOARD_VNDK_VERSION := current
-
-# Properties
-TARGET_SYSTEM_PROP := build/make/target/board/treble_system.prop
-BOARD_PROPERTY_OVERRIDES_SPLIT_ENABLED := true
-
-# Bootloader, kernel and recovery are not part of generic AOSP image
-TARGET_NO_BOOTLOADER := true
-TARGET_NO_KERNEL := true
-
-# system.img is always ext4 with sparse option
-# GSI also includes make_f2fs to support userdata parition in f2fs
-# for some devices
-TARGET_USERIMAGES_USE_EXT4 := true
-TARGET_USERIMAGES_USE_F2FS := true
-TARGET_USERIMAGES_SPARSE_EXT_DISABLED := false
-
-# Enable dynamic system image size and reserved 64MB in it.
-BOARD_SYSTEMIMAGE_PARTITION_RESERVED_SIZE := 67108864
-
-# Generic AOSP image always requires separate vendor.img
-TARGET_COPY_OUT_VENDOR := vendor
-
-# Android generic system image always create metadata partition
-BOARD_USES_METADATA_PARTITION := true
-
-# Set emulator framebuffer display device buffer count to 3
-NUM_FRAMEBUFFER_SURFACE_BUFFERS := 3
-
-# Audio
-USE_XML_AUDIO_POLICY_CONF := 1
-
-# Android Verified Boot (AVB):
-#   1) Sets BOARD_AVB_ENABLE to sign the GSI image.
-#   2) Sets AVB_VBMETA_IMAGE_FLAGS_VERIFICATION_DISABLED (--flag 2) in
-#      vbmeta.img to disable AVB verification.
-#
-# To disable AVB for GSI, use the vbmeta.img and the GSI together.
-# To enable AVB for GSI, include the GSI public key into the device-specific
-# vbmeta.img.
-BOARD_AVB_ENABLE := true
-BOARD_AVB_ROLLBACK_INDEX := $(PLATFORM_SECURITY_PATCH_TIMESTAMP)
-BOARD_AVB_MAKE_VBMETA_IMAGE_ARGS += --flag 2
-
-# Enable chain partition for system.
-BOARD_AVB_SYSTEM_KEY_PATH := external/avb/test/data/testkey_rsa2048.pem
-BOARD_AVB_SYSTEM_ALGORITHM := SHA256_RSA2048
-BOARD_AVB_SYSTEM_ROLLBACK_INDEX := $(PLATFORM_SECURITY_PATCH_TIMESTAMP)
-BOARD_AVB_SYSTEM_ROLLBACK_INDEX_LOCATION := 1
diff --git a/target/board/treble_common_32.mk b/target/board/treble_common_32.mk
deleted file mode 100644
index b66c41e..0000000
--- a/target/board/treble_common_32.mk
+++ /dev/null
@@ -1,17 +0,0 @@
-#
-# Copyright (C) 2017 The Android Open-Source Project
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#      http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-#
-
-include build/make/target/board/treble_common.mk
diff --git a/target/board/treble_common_64.mk b/target/board/treble_common_64.mk
deleted file mode 100644
index 8980dfd..0000000
--- a/target/board/treble_common_64.mk
+++ /dev/null
@@ -1,20 +0,0 @@
-#
-# Copyright (C) 2017 The Android Open-Source Project
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#      http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-#
-
-include build/make/target/board/treble_common.mk
-
-# Enable 64-bits binder
-TARGET_USES_64_BIT_BINDER := true
diff --git a/target/board/treble_system.prop b/target/board/treble_system.prop
deleted file mode 100644
index 0c04a95..0000000
--- a/target/board/treble_system.prop
+++ /dev/null
@@ -1,8 +0,0 @@
-# GSI always generate dex pre-opt in system image
-ro.cp_system_other_odex=0
-
-# GSI always disables adb authentication
-ro.adb.secure=0
-
-# TODO(b/78105955): disable privapp_permissions checking before the bug solved
-ro.control_privapp_permissions=disable
diff --git a/target/product/aosp_arm64_a.mk b/target/product/aosp_arm64_a.mk
index 3c7af33..b1c4b7d 100644
--- a/target/product/aosp_arm64_a.mk
+++ b/target/product/aosp_arm64_a.mk
@@ -17,7 +17,7 @@
 # PRODUCT_PROPERTY_OVERRIDES cannot be used here because sysprops will be at
 # /vendor/[build|default].prop when build split is on. In order to have sysprops
 # on the generic system image, place them in build/make/target/board/
-# treble_system.prop.
+# gsi_system.prop.
 
 include build/make/target/product/treble_common_64.mk
 
diff --git a/target/product/aosp_arm64_ab.mk b/target/product/aosp_arm64_ab.mk
index d389c74..92f5055 100644
--- a/target/product/aosp_arm64_ab.mk
+++ b/target/product/aosp_arm64_ab.mk
@@ -17,7 +17,7 @@
 # PRODUCT_PROPERTY_OVERRIDES cannot be used here because sysprops will be at
 # /vendor/[build|default].prop when build split is on. In order to have sysprops
 # on the generic system image, place them in build/make/target/board/
-# treble_system.prop.
+# gsi_system.prop.
 
 # aosp_arm64_ab-userdebug is a Legacy GSI for the devices with:
 # - ARM 64 bits user space
diff --git a/target/product/aosp_arm_a.mk b/target/product/aosp_arm_a.mk
index 3060fa9..d89a326 100644
--- a/target/product/aosp_arm_a.mk
+++ b/target/product/aosp_arm_a.mk
@@ -17,7 +17,7 @@
 # PRODUCT_PROPERTY_OVERRIDES cannot be used here because sysprops will be at
 # /vendor/[build|default].prop when build split is on. In order to have sysprops
 # on the generic system image, place them in build/make/target/board/
-# treble_system.prop.
+# gsi_system.prop.
 
 include build/make/target/product/treble_common_32.mk
 
diff --git a/target/product/aosp_arm_ab.mk b/target/product/aosp_arm_ab.mk
index 5845d3b..b35e517 100644
--- a/target/product/aosp_arm_ab.mk
+++ b/target/product/aosp_arm_ab.mk
@@ -17,7 +17,7 @@
 # PRODUCT_PROPERTY_OVERRIDES cannot be used here because sysprops will be at
 # /vendor/[build|default].prop when build split is on. In order to have sysprops
 # on the generic system image, place them in build/make/target/board/
-# treble_system.prop.
+# gsi_system.prop.
 
 # aosp_arm_ab-userdebug is a Legacy GSI for the devices with:
 # - ARM 32 bits user space
diff --git a/target/product/aosp_x86_64_a.mk b/target/product/aosp_x86_64_a.mk
index a7fb740..6b6785a 100644
--- a/target/product/aosp_x86_64_a.mk
+++ b/target/product/aosp_x86_64_a.mk
@@ -17,7 +17,7 @@
 # PRODUCT_PROPERTY_OVERRIDES cannot be used here because sysprops will be at
 # /vendor/[build|default].prop when build split is on. In order to have sysprops
 # on the generic system image, place them in build/make/target/board/
-# treble_system.prop.
+# gsi_system.prop.
 
 include build/make/target/product/treble_common_64.mk
 
diff --git a/target/product/aosp_x86_64_ab.mk b/target/product/aosp_x86_64_ab.mk
index d9163d7..35bf61a 100644
--- a/target/product/aosp_x86_64_ab.mk
+++ b/target/product/aosp_x86_64_ab.mk
@@ -17,7 +17,7 @@
 # PRODUCT_PROPERTY_OVERRIDES cannot be used here because sysprops will be at
 # /vendor/[build|default].prop when build split is on. In order to have sysprops
 # on the generic system image, place them in build/make/target/board/
-# treble_system.prop.
+# gsi_system.prop.
 
 # aosp_x86_64_ab-userdebug is a Legacy GSI for the devices with:
 # - x86 64 bits user space
diff --git a/target/product/aosp_x86_a.mk b/target/product/aosp_x86_a.mk
index 9ed2995..99ed7e4 100644
--- a/target/product/aosp_x86_a.mk
+++ b/target/product/aosp_x86_a.mk
@@ -17,7 +17,7 @@
 # PRODUCT_PROPERTY_OVERRIDES cannot be used here because sysprops will be at
 # /vendor/[build|default].prop when build split is on. In order to have sysprops
 # on the generic system image, place them in build/make/target/board/
-# treble_system.prop.
+# gsi_system.prop.
 
 include build/make/target/product/treble_common_32.mk
 
diff --git a/target/product/aosp_x86_ab.mk b/target/product/aosp_x86_ab.mk
index 4fff3d1..185e2f0 100644
--- a/target/product/aosp_x86_ab.mk
+++ b/target/product/aosp_x86_ab.mk
@@ -17,7 +17,7 @@
 # PRODUCT_PROPERTY_OVERRIDES cannot be used here because sysprops will be at
 # /vendor/[build|default].prop when build split is on. In order to have sysprops
 # on the generic system image, place them in build/make/target/board/
-# treble_system.prop.
+# gsi_system.prop.
 
 # aosp_x86_ab-userdebug is a Legacy GSI for the devices with:
 # - x86 32 bits user space
diff --git a/target/product/base_system.mk b/target/product/base_system.mk
index 428e284..07fea22 100644
--- a/target/product/base_system.mk
+++ b/target/product/base_system.mk
@@ -16,6 +16,7 @@
 
 # Base modules and settings for the system partition.
 PRODUCT_PACKAGES += \
+    abb \
     adb \
     adbd \
     am \
@@ -48,7 +49,6 @@
     bu \
     bugreport \
     bugreportz \
-    cameraserver \
     charger \
     cmd \
     com.android.conscrypt \
@@ -82,7 +82,6 @@
     heapprofd_client \
     gatekeeperd \
     gpuservice \
-    healthd \
     hid \
     hwservicemanager \
     idmap \
@@ -195,6 +194,7 @@
     locksettings \
     logcat \
     logd \
+    lpdump \
     lshal \
     mdnsd \
     media \
@@ -206,10 +206,12 @@
     MediaProvider \
     mediaserver \
     mke2fs \
+    ModuleMetadata \
     monkey \
     mtpd \
     ndc \
     netd \
+    NetworkStack \
     org.apache.http.legacy \
     perfetto \
     ping \
@@ -314,10 +316,7 @@
 # Packages included only for eng or userdebug builds, previously debug tagged
 PRODUCT_PACKAGES_DEBUG := \
     adb_keys \
-    apex.test.key \
     arping \
-    com.android.apex.test_package.key \
-    com.android.apex.test_package.preinstall.key \
     iotop \
     iw \
     logpersist.start \
diff --git a/target/product/base_vendor.mk b/target/product/base_vendor.mk
index 9bb45d1..1bb4bee 100644
--- a/target/product/base_vendor.mk
+++ b/target/product/base_vendor.mk
@@ -53,6 +53,10 @@
     vndservice \
     vndservicemanager \
 
+# Base modules and settings for the product partition.
+PRODUCT_PACKAGES += \
+    healthd \
+
 # VINTF data for vendor image
 PRODUCT_PACKAGES += \
     device_manifest.xml \
diff --git a/target/product/go_defaults_common.mk b/target/product/go_defaults_common.mk
index 18907c1..06bdec9 100644
--- a/target/product/go_defaults_common.mk
+++ b/target/product/go_defaults_common.mk
@@ -61,6 +61,10 @@
 # Do not generate libartd.
 PRODUCT_ART_TARGET_INCLUDE_DEBUG_BUILD := false
 
+# Do not spin up a separate process for the network stack on go devices, use an in-process lib.
+PRODUCT_PACKAGES += NetworkStackLib
+PRODUCT_SYSTEM_SERVER_JARS += NetworkStackLib
+
 # Strip the local variable table and the local variable type table to reduce
 # the size of the system image. This has no bearing on stack traces, but will
 # leave less information available via JDWP.
diff --git a/target/product/gsi/current.txt b/target/product/gsi/current.txt
index 0b99000..17d2f1b 100644
--- a/target/product/gsi/current.txt
+++ b/target/product/gsi/current.txt
@@ -118,7 +118,9 @@
 VNDK-core: android.hardware.neuralnetworks@1.2.so
 VNDK-core: android.hardware.nfc@1.0.so
 VNDK-core: android.hardware.nfc@1.1.so
+VNDK-core: android.hardware.nfc@1.2.so
 VNDK-core: android.hardware.oemlock@1.0.so
+VNDK-core: android.hardware.power.stats@1.0.so
 VNDK-core: android.hardware.power@1.0.so
 VNDK-core: android.hardware.power@1.1.so
 VNDK-core: android.hardware.power@1.2.so
diff --git a/target/product/handheld_system.mk b/target/product/handheld_system.mk
index a961d1e..acafe80 100644
--- a/target/product/handheld_system.mk
+++ b/target/product/handheld_system.mk
@@ -36,52 +36,34 @@
     Bluetooth \
     BluetoothMidiService \
     BookmarkProvider \
-    Browser2 \
     BuiltInPrintService \
-    Calendar \
     CalendarProvider \
-    Camera2 \
+    cameraserver \
     CaptivePortalLogin \
     CertInstaller \
     clatd \
     clatd.conf \
-    Contacts \
-    DeskClock \
     DocumentsUI \
     DownloadProviderUi \
     EasterEgg \
-    Email \
     ExactCalculator \
     ExternalStorageProvider \
     FusedLocation \
-    Gallery2 \
-    Home \
     InputDevices \
     KeyChain \
-    LatinIME \
-    Launcher3QuickStep \
     librs_jni \
     ManagedProvisioning \
     MmsService \
     MtpDocumentsProvider \
-    Music \
     MusicFX \
     NfcNci \
-    OneTimeInitializer \
     PacProcessor \
-    PrintRecommendationService \
     PrintSpooler \
-    Provision \
     ProxyHandler \
-    QuickSearchBox \
     screenrecord \
     SecureElement \
-    Settings \
-    SettingsIntelligence \
     SharedStorageBackup \
     SimAppDialog \
-    StorageManager \
-    SystemUI \
     Telecom \
     TelephonyProvider \
     TeleService \
@@ -89,7 +71,6 @@
     UserDictionaryProvider \
     VpnDialogs \
     vr \
-    WallpaperCropper \
 
 
 PRODUCT_SYSTEM_SERVER_APPS += \
diff --git a/target/product/handheld_vendor.mk b/target/product/handheld_vendor.mk
index 0f73875..b9970e9 100644
--- a/target/product/handheld_vendor.mk
+++ b/target/product/handheld_vendor.mk
@@ -19,6 +19,8 @@
 # it definitely doesn't belong on other types of devices (if it
 # does, use base_vendor.mk).
 $(call inherit-product, $(SRC_TARGET_DIR)/product/media_vendor.mk)
+
+# /vendor packages
 PRODUCT_PACKAGES += \
     audio.primary.default \
     DisplayCutoutEmulationCornerOverlay \
@@ -28,3 +30,25 @@
     power.default \
     SysuiDarkThemeOverlay \
     vibrator.default \
+
+# /product packages
+PRODUCT_PACKAGES += \
+    Browser2 \
+    Calendar \
+    Camera2 \
+    Contacts \
+    DeskClock \
+    Email \
+    Gallery2 \
+    LatinIME \
+    Launcher3QuickStep \
+    Music \
+    OneTimeInitializer \
+    PrintRecommendationService \
+    Provision \
+    QuickSearchBox \
+    Settings \
+    SettingsIntelligence \
+    StorageManager \
+    SystemUI \
+    WallpaperCropper \
diff --git a/target/product/languages_default.mk b/target/product/languages_default.mk
new file mode 100644
index 0000000..a13a23c
--- /dev/null
+++ b/target/product/languages_default.mk
@@ -0,0 +1,105 @@
+#
+# Copyright (C) 2009 The Android Open Source Project
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+# This is a build configuration that just contains a list of languages, with
+# en_US set as the default language.
+PRODUCT_LOCALES := \
+        en_US \
+        af_ZA \
+        am_ET \
+        ar_EG \
+        ar_XB \
+        as_IN \
+        az_AZ \
+        be_BY \
+        bg_BG \
+        bn_BD \
+        bs_BA \
+        ca_ES \
+        cs_CZ \
+        da_DK \
+        de_DE \
+        el_GR \
+        en_AU \
+        en_CA \
+        en_GB \
+        en_IN \
+        en_XA \
+        es_ES \
+        es_US \
+        et_EE \
+        eu_ES \
+        fa_IR \
+        fi_FI \
+        fr_CA \
+        fr_FR \
+        gl_ES \
+        gu_IN \
+        hi_IN \
+        hr_HR \
+        hu_HU \
+        hy_AM \
+        in_ID \
+        is_IS \
+        it_IT \
+        iw_IL \
+        ja_JP \
+        ka_GE \
+        kk_KZ \
+        km_KH \
+        kn_IN \
+        ko_KR \
+        ky_KG \
+        lo_LA \
+        lt_LT \
+        lv_LV \
+        mk_MK \
+        ml_IN \
+        mn_MN \
+        mr_IN \
+        ms_MY \
+        my_MM \
+        nb_NO \
+        ne_NP \
+        nl_NL \
+        or_IN \
+        pa_IN \
+        pl_PL \
+        pt_BR \
+        pt_PT \
+        ro_RO \
+        ru_RU \
+        si_LK \
+        sk_SK \
+        sl_SI \
+        sq_AL \
+        sr_Latn_RS \
+        sr_RS \
+        sv_SE \
+        sw_TZ \
+        ta_IN \
+        te_IN \
+        th_TH \
+        tl_PH \
+        tr_TR \
+        uk_UA \
+        ur_PK \
+        uz_UZ \
+        vi_VN \
+        zh_CN \
+        zh_HK \
+        zh_TW \
+        zu_ZA \
diff --git a/target/product/languages_full.mk b/target/product/languages_full.mk
index 5f3795f..43a40a7 100644
--- a/target/product/languages_full.mk
+++ b/target/product/languages_full.mk
@@ -14,94 +14,9 @@
 # limitations under the License.
 #
 
-# This is a build configuration that just contains a list of languages.
-#
-# These are all the locales that have translations.
-PRODUCT_LOCALES := \
-        en_US \
-        af_ZA \
-        am_ET \
-        ar_EG \
-        ar_XB \
-        as_IN \
-        az_AZ \
-        be_BY \
-        bg_BG \
-        bn_BD \
-        bs_BA \
-        ca_ES \
-        cs_CZ \
-        da_DK \
-        de_DE \
-        el_GR \
-        en_AU \
-        en_CA \
-        en_GB \
-        en_IN \
-        en_XA \
-        en_XC \
-        es_ES \
-        es_US \
-        et_EE \
-        eu_ES \
-        fa_IR \
-        fi_FI \
-        fr_CA \
-        fr_FR \
-        gl_ES \
-        gu_IN \
-        hi_IN \
-        hr_HR \
-        hu_HU \
-        hy_AM \
-        in_ID \
-        is_IS \
-        it_IT \
-        iw_IL \
-        ja_JP \
-        ka_GE \
-        kk_KZ \
-        km_KH \
-        kn_IN \
-        ko_KR \
-        ky_KG \
-        lo_LA \
-        lt_LT \
-        lv_LV \
-        mk_MK \
-        ml_IN \
-        mn_MN \
-        mr_IN \
-        ms_MY \
-        my_MM \
-        nb_NO \
-        ne_NP \
-        nl_NL \
-        or_IN \
-        pa_IN \
-        pl_PL \
-        pt_BR \
-        pt_PT \
-        ro_RO \
-        ru_RU \
-        si_LK \
-        sk_SK \
-        sl_SI \
-        sq_AL \
-        sr_Latn_RS \
-        sr_RS \
-        sv_SE \
-        sw_TZ \
-        ta_IN \
-        te_IN \
-        th_TH \
-        tl_PH \
-        tr_TR \
-        uk_UA \
-        ur_PK \
-        uz_UZ \
-        vi_VN \
-        zh_CN \
-        zh_HK \
-        zh_TW \
-        zu_ZA
+# This is a build configuration that contains the default list of languages,
+# as well as the en_XC pseudo-locale, which is useful for localization test
+# builds.
+
+$(call inherit-product, $(SRC_TARGET_DIR)/product/languages_default.mk)
+PRODUCT_LOCALES += en_XC
diff --git a/target/product/languages_small.mk b/target/product/languages_small.mk
deleted file mode 100644
index d695ca8..0000000
--- a/target/product/languages_small.mk
+++ /dev/null
@@ -1,24 +0,0 @@
-#
-# Copyright (C) 2009 The Android Open Source Project
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#      http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-#
-
-# This is a build configuration that just contains a list of languages.
-# It helps in situations where laugnages must come first in the list,
-# mostly because screen densities interfere with the list of locales and
-# the system misbehaves when a density is the first locale.
-
-# This is the list of languages that originally shipped on ADP1
-
-PRODUCT_LOCALES := en_US en_GB fr_FR it_IT de_DE es_ES
diff --git a/target/product/mainline.mk b/target/product/mainline.mk
new file mode 100644
index 0000000..44dcd60
--- /dev/null
+++ b/target/product/mainline.mk
@@ -0,0 +1,21 @@
+#
+# Copyright (C) 2019 The Android Open Source Project
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+# Makefile including the mainline system image, and the relevant AOSP portions
+# for the other partitions.
+$(call inherit-product, $(SRC_TARGET_DIR)/product/mainline_system.mk)
+$(call inherit-product, $(SRC_TARGET_DIR)/product/handheld_vendor.mk)
+$(call inherit-product, $(SRC_TARGET_DIR)/product/telephony_vendor.mk)
diff --git a/target/product/mainline_arm64.mk b/target/product/mainline_arm64.mk
index f93d7e4..6122ac1 100644
--- a/target/product/mainline_arm64.mk
+++ b/target/product/mainline_arm64.mk
@@ -15,9 +15,7 @@
 #
 
 $(call inherit-product, $(SRC_TARGET_DIR)/product/core_64_bit.mk)
-$(call inherit-product, $(SRC_TARGET_DIR)/product/mainline_system.mk)
-$(call inherit-product, $(SRC_TARGET_DIR)/product/handheld_vendor.mk)
-$(call inherit-product, $(SRC_TARGET_DIR)/product/telephony_vendor.mk)
+$(call inherit-product, $(SRC_TARGET_DIR)/product/mainline.mk)
 
 PRODUCT_NAME := mainline_arm64
 PRODUCT_DEVICE := generic_arm64
@@ -32,3 +30,40 @@
   root/init.zygote64_32.rc \
   system/etc/seccomp_policy/crash_dump.arm.policy \
   system/etc/seccomp_policy/mediacodec.policy \
+
+# Modules that are to be moved to /product
+PRODUCT_ARTIFACT_PATH_REQUIREMENT_WHITELIST += \
+  system/app/Browser2/Browser2.apk \
+  system/app/Calendar/Calendar.apk \
+  system/app/Camera2/Camera2.apk \
+  system/app/DeskClock/DeskClock.apk \
+  system/app/Email/Email.apk \
+  system/app/Gallery2/Gallery2.apk \
+  system/app/LatinIME/LatinIME.apk \
+  system/app/LatinIME/oat/arm64/LatinIME.odex \
+  system/app/LatinIME/oat/arm64/LatinIME.vdex \
+  system/app/Music/Music.apk \
+  system/app/PrintRecommendationService/PrintRecommendationService.apk \
+  system/app/QuickSearchBox/QuickSearchBox.apk \
+  system/bin/healthd \
+  system/etc/init/healthd.rc \
+  system/etc/vintf/manifest/manifest_healthd.xml \
+  system/lib64/libjni_eglfence.so \
+  system/lib64/libjni_filtershow_filters.so \
+  system/lib64/libjni_jpegstream.so \
+  system/lib64/libjni_jpegutil.so \
+  system/lib64/libjni_latinime.so \
+  system/lib64/libjni_tinyplanet.so \
+  system/priv-app/CarrierConfig/CarrierConfig.apk \
+  system/priv-app/Contacts/Contacts.apk \
+  system/priv-app/Dialer/Dialer.apk \
+  system/priv-app/Launcher3QuickStep/Launcher3QuickStep.apk \
+  system/priv-app/OneTimeInitializer/OneTimeInitializer.apk \
+  system/priv-app/Provision/Provision.apk \
+  system/priv-app/Settings/Settings.apk \
+  system/priv-app/SettingsIntelligence/SettingsIntelligence.apk \
+  system/priv-app/StorageManager/StorageManager.apk \
+  system/priv-app/SystemUI/SystemUI.apk \
+  system/priv-app/SystemUI/oat/arm64/SystemUI.odex \
+  system/priv-app/SystemUI/oat/arm64/SystemUI.vdex \
+  system/priv-app/WallpaperCropper/WallpaperCropper.apk \
diff --git a/target/product/mainline_system.mk b/target/product/mainline_system.mk
index c41e1d7..b9b422f 100644
--- a/target/product/mainline_system.mk
+++ b/target/product/mainline_system.mk
@@ -17,6 +17,9 @@
 # This makefile is the basis of a generic system image for a handheld device.
 $(call inherit-product, $(SRC_TARGET_DIR)/product/handheld_system.mk)
 $(call inherit-product, $(SRC_TARGET_DIR)/product/telephony_system.mk)
+$(call inherit-product, $(SRC_TARGET_DIR)/product/languages_default.mk)
+# Add adb keys to debuggable AOSP builds (if they exist)
+$(call inherit-product-if-exists, vendor/google/security/adb/vendor_key.mk)
 
 # Shared java libs
 PRODUCT_PACKAGES += \
@@ -31,6 +34,7 @@
     RcsService \
     SafetyRegulatoryInfo \
     Stk \
+    Tag \
     TimeZoneUpdater \
 
 # Binaries
@@ -71,6 +75,7 @@
     android.hardware.radio.deprecated@1.0 \
     android.hardware.secure_element@1.0 \
     android.hardware.tests.libhwbinder@1.0-impl \
+    android.hardware.wifi@1.0 \
     android.hidl.base@1.0 \
     libaudio-resampler \
     liblogwrap \
@@ -97,8 +102,6 @@
 # Enable dynamic partition size
 PRODUCT_USE_DYNAMIC_PARTITION_SIZE := true
 
-PRODUCT_LOCALES := en_US af_ZA am_ET ar_EG as_IN az_AZ be_BY bg_BG bn_BD bs_BA ca_ES cs_CZ da_DK de_DE el_GR en_AU en_CA en_GB en_IN es_ES es_US et_EE eu_ES fa_IR fi_FI fr_CA fr_FR gl_ES gu_IN hi_IN hr_HR hu_HU hy_AM in_ID is_IS it_IT iw_IL ja_JP ka_GE kk_KZ km_KH ko_KR ky_KG lo_LA lt_LT lv_LV km_MH kn_IN mn_MN ml_IN mk_MK mr_IN ms_MY my_MM ne_NP nb_NO nl_NL or_IN pa_IN pl_PL pt_BR pt_PT ro_RO ru_RU si_LK sk_SK sl_SI sq_AL sr_Latn_RS sr_RS sv_SE sw_TZ ta_IN te_IN th_TH tl_PH tr_TR uk_UA ur_PK uz_UZ vi_VN zh_CN zh_HK zh_TW zu_ZA en_XA ar_XB
-
 PRODUCT_NAME := mainline_system
 PRODUCT_BRAND := generic
 
diff --git a/target/product/media_vendor.mk b/target/product/media_vendor.mk
index 1db0b58..f30e6f3 100644
--- a/target/product/media_vendor.mk
+++ b/target/product/media_vendor.mk
@@ -20,6 +20,11 @@
 # base_vendor.mk.
 $(call inherit-product, $(SRC_TARGET_DIR)/product/base_vendor.mk)
 
+# /vendor packages
 PRODUCT_PACKAGES += \
     libaudiopreprocessing \
     libwebrtc_audio_preprocessing \
+
+# /product packages
+PRODUCT_PACKAGES += \
+    webview \
diff --git a/target/product/telephony_system.mk b/target/product/telephony_system.mk
index 0b1e8a2..e30f036 100644
--- a/target/product/telephony_system.mk
+++ b/target/product/telephony_system.mk
@@ -19,9 +19,7 @@
 
 PRODUCT_PACKAGES := \
     ANS \
-    CarrierConfig \
     CarrierDefaultApp \
-    Dialer \
     CallLogBackup \
     CellBroadcastReceiver \
     EmergencyInfo \
diff --git a/target/product/telephony_vendor.mk b/target/product/telephony_vendor.mk
index bddd383..4cff16d 100644
--- a/target/product/telephony_vendor.mk
+++ b/target/product/telephony_vendor.mk
@@ -17,7 +17,13 @@
 # This is the list of modules that are specific to products that have telephony
 # hardware, and install outside the system partition.
 
+# /vendor packages
 PRODUCT_PACKAGES := \
     rild \
 
+# /product packages
+PRODUCT_PACKAGES += \
+    CarrierConfig \
+    Dialer \
+
 PRODUCT_COPY_FILES := \
diff --git a/target/product/treble_common.mk b/target/product/treble_common.mk
index 0408028..7642876 100644
--- a/target/product/treble_common.mk
+++ b/target/product/treble_common.mk
@@ -38,7 +38,7 @@
 # Telephony:
 #   Provide a default APN configuration
 PRODUCT_COPY_FILES += \
-    device/generic/goldfish/data/etc/apns-conf.xml:system/etc/apns-conf.xml
+    device/sample/etc/apns-full-conf.xml:system/etc/apns-conf.xml
 
 # NFC:
 #   Provide default libnfc-nci.conf file for devices that does not have one in
diff --git a/tools/Android.mk b/tools/Android.mk
deleted file mode 100644
index c05d681..0000000
--- a/tools/Android.mk
+++ /dev/null
@@ -1,23 +0,0 @@
-#
-# Copyright (C) 2010 The Android Open Source Project
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#      http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-#
-
-LOCAL_PATH := $(call my-dir)
-
-# Only if this Android.mk was included not by a symlink should it be used.
-# This facilitates the transition away from symlinks: b/64397960
-ifeq ($(LOCAL_PATH),build/make/tools)
-include $(call all-makefiles-under,$(LOCAL_PATH))
-endif
diff --git a/tools/buildinfo.sh b/tools/buildinfo.sh
index c2e6f85..b76c089 100755
--- a/tools/buildinfo.sh
+++ b/tools/buildinfo.sh
@@ -8,6 +8,7 @@
 echo "ro.build.version.incremental=$BUILD_NUMBER"
 echo "ro.build.version.sdk=$PLATFORM_SDK_VERSION"
 echo "ro.build.version.preview_sdk=$PLATFORM_PREVIEW_SDK_VERSION"
+echo "ro.build.version.preview_sdk_fingerprint=$PLATFORM_PREVIEW_SDK_FINGERPRINT"
 echo "ro.build.version.codename=$PLATFORM_VERSION_CODENAME"
 echo "ro.build.version.all_codenames=$PLATFORM_VERSION_ALL_CODENAMES"
 echo "ro.build.version.release=$PLATFORM_VERSION"
diff --git a/tools/droiddoc/Android.mk b/tools/droiddoc/Android.mk
deleted file mode 100644
index ff08edc..0000000
--- a/tools/droiddoc/Android.mk
+++ /dev/null
@@ -1,17 +0,0 @@
-# Copyright (C) 2008 The Android Open Source Project
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#      http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-
-LOCAL_PATH := $(call my-dir)
-
-# Droiddoc is now Doclava -- See external/doclava.
diff --git a/tools/releasetools/add_img_to_target_files.py b/tools/releasetools/add_img_to_target_files.py
index 1872a58..da5ea4a 100755
--- a/tools/releasetools/add_img_to_target_files.py
+++ b/tools/releasetools/add_img_to_target_files.py
@@ -859,11 +859,12 @@
     banner("vbmeta")
     AddVBMeta(output_zip, partitions, "vbmeta", vbmeta_partitions)
 
-  if OPTIONS.info_dict.get("build_super_partition"):
+  if OPTIONS.info_dict.get("build_super_partition") == "true":
     banner("super_empty")
     AddSuperEmpty(output_zip)
 
-    if OPTIONS.info_dict.get("dynamic_partition_retrofit") == "true":
+    if OPTIONS.info_dict.get(
+        "build_retrofit_dynamic_partitions_ota_package") == "true":
       banner("super split images")
       AddSuperSplit(output_zip)
 
diff --git a/tools/releasetools/blockimgdiff.py b/tools/releasetools/blockimgdiff.py
index b5e01d3..80d4023 100644
--- a/tools/releasetools/blockimgdiff.py
+++ b/tools/releasetools/blockimgdiff.py
@@ -471,6 +471,23 @@
 
     # Ensure the runtime stash size is under the limit.
     if common.OPTIONS.cache_size is not None:
+      stash_limit = (common.OPTIONS.cache_size *
+                     common.OPTIONS.stash_threshold / self.tgt.blocksize)
+      # Ignore the stash limit and calculate the maximum simultaneously stashed
+      # blocks needed.
+      _, max_stashed_blocks = self.ReviseStashSize(ignore_stash_limit=True)
+
+      # We cannot stash more blocks than the stash limit simultaneously. As a
+      # result, some 'diff' commands will be converted to new; leading to an
+      # unintended large package. To mitigate this issue, we can carefully
+      # choose the transfers for conversion. The number '1024' can be further
+      # tweaked here to balance the package size and build time.
+      if max_stashed_blocks > stash_limit + 1024:
+        self.SelectAndConvertDiffTransfersToNew()
+        # Regenerate the sequence as the graph has changed.
+        self.FindSequenceForTransfers()
+
+      # Revise the stash size again to keep the size under limit.
       self.ReviseStashSize()
 
     # Double-check our work.
@@ -700,7 +717,21 @@
           "max stashed blocks: %d  (%d bytes), limit: <unknown>\n",
           max_stashed_blocks, self._max_stashed_size)
 
-  def ReviseStashSize(self):
+  def ReviseStashSize(self, ignore_stash_limit=False):
+    """ Revises the transfers to keep the stash size within the size limit.
+
+    Iterates through the transfer list and calculates the stash size each
+    transfer generates. Converts the affected transfers to new if we reach the
+    stash limit.
+
+    Args:
+      ignore_stash_limit: Ignores the stash limit and calculates the max
+      simultaneous stashed blocks instead. No change will be made to the
+      transfer list with this flag.
+
+    Return:
+      A tuple of (tgt blocks converted to new, max stashed blocks)
+    """
     logger.info("Revising stash size...")
     stash_map = {}
 
@@ -715,16 +746,19 @@
       for stash_raw_id, _ in xf.use_stash:
         stash_map[stash_raw_id] += (xf,)
 
-    # Compute the maximum blocks available for stash based on /cache size and
-    # the threshold.
-    cache_size = common.OPTIONS.cache_size
-    stash_threshold = common.OPTIONS.stash_threshold
-    max_allowed = cache_size * stash_threshold / self.tgt.blocksize
+    max_allowed_blocks = None
+    if not ignore_stash_limit:
+      # Compute the maximum blocks available for stash based on /cache size and
+      # the threshold.
+      cache_size = common.OPTIONS.cache_size
+      stash_threshold = common.OPTIONS.stash_threshold
+      max_allowed_blocks = cache_size * stash_threshold / self.tgt.blocksize
 
     # See the comments for 'stashes' in WriteTransfers().
     stashes = {}
     stashed_blocks = 0
     new_blocks = 0
+    max_stashed_blocks = 0
 
     # Now go through all the commands. Compute the required stash size on the
     # fly. If a command requires excess stash than available, it deletes the
@@ -741,7 +775,7 @@
         if sh not in stashes:
           stashed_blocks_after += sr.size()
 
-        if stashed_blocks_after > max_allowed:
+        if max_allowed_blocks and stashed_blocks_after > max_allowed_blocks:
           # We cannot stash this one for a later command. Find out the command
           # that will use this stash and replace the command with "new".
           use_cmd = stash_map[stash_raw_id][2]
@@ -754,15 +788,21 @@
           else:
             stashes[sh] = 1
           stashed_blocks = stashed_blocks_after
+          max_stashed_blocks = max(max_stashed_blocks, stashed_blocks)
 
       # "move" and "diff" may introduce implicit stashes in BBOTA v3. Prior to
       # ComputePatches(), they both have the style of "diff".
       if xf.style == "diff":
         assert xf.tgt_ranges and xf.src_ranges
         if xf.src_ranges.overlaps(xf.tgt_ranges):
-          if stashed_blocks + xf.src_ranges.size() > max_allowed:
+          if (max_allowed_blocks and
+              stashed_blocks + xf.src_ranges.size() > max_allowed_blocks):
             replaced_cmds.append(xf)
             logger.info("%10d  %9s  %s", xf.src_ranges.size(), "implicit", xf)
+          else:
+            # The whole source ranges will be stashed for implicit stashes.
+            max_stashed_blocks = max(max_stashed_blocks,
+                                     stashed_blocks + xf.src_ranges.size())
 
       # Replace the commands in replaced_cmds with "new"s.
       for cmd in replaced_cmds:
@@ -791,7 +831,7 @@
     logger.info(
         "  Total %d blocks (%d bytes) are packed as new blocks due to "
         "insufficient cache size.", new_blocks, num_of_bytes)
-    return new_blocks
+    return new_blocks, max_stashed_blocks
 
   def ComputePatches(self, prefix):
     logger.info("Reticulating splines...")
@@ -1299,6 +1339,53 @@
 
     return patches
 
+  def SelectAndConvertDiffTransfersToNew(self):
+    """Converts the diff transfers to reduce the max simultaneous stash.
+
+    Since the 'new' data is compressed with deflate, we can select the 'diff'
+    transfers for conversion by comparing its patch size with the size of the
+    compressed data. Ideally, we want to convert the transfers with a small
+    size increase, but using a large number of stashed blocks.
+    """
+
+    logger.info("Selecting diff commands to convert to new.")
+    diff_queue = []
+    for xf in self.transfers:
+      if xf.style == "diff" and xf.src_sha1 != xf.tgt_sha1:
+        use_imgdiff = self.CanUseImgdiff(xf.tgt_name, xf.tgt_ranges,
+                                         xf.src_ranges)
+        diff_queue.append((xf.order, use_imgdiff, len(diff_queue)))
+
+    # Remove the 'move' transfers, and compute the patch & compressed size
+    # for the remaining.
+    result = self.ComputePatchesForInputList(diff_queue, True)
+
+    removed_stashed_blocks = 0
+    for xf_index, patch_info, compressed_size in result:
+      xf = self.transfers[xf_index]
+      if not xf.patch_info:
+        xf.patch_info = patch_info
+
+      size_ratio = len(xf.patch_info.content) * 100.0 / compressed_size
+      diff_style = "imgdiff" if xf.patch_info.imgdiff else "bsdiff"
+      logger.info("%s, target size: %d, style: %s, patch size: %d,"
+                  " compression_size: %d, ratio %.2f%%", xf.tgt_name,
+                  xf.tgt_ranges.size(), diff_style,
+                  len(xf.patch_info.content), compressed_size, size_ratio)
+
+      # Convert the transfer to new if the compressed size is smaller or equal.
+      # We don't need to maintain the stash_before lists here because the
+      # graph will be regenerated later.
+      if len(xf.patch_info.content) >= compressed_size:
+        removed_stashed_blocks += sum(sr.size() for _, sr in xf.use_stash)
+        logger.info("Converting %s to new", xf.tgt_name)
+        xf.ConvertToNew()
+
+    # TODO(xunchang) convert more transfers by sorting:
+    # (compressed size - patch_size) / used_stashed_blocks
+
+    logger.info("Removed %d stashed blocks", removed_stashed_blocks)
+
   def FindTransfers(self):
     """Parse the file_map to generate all the transfers."""
 
diff --git a/tools/releasetools/build_image.py b/tools/releasetools/build_image.py
index 146b868..d710603 100755
--- a/tools/releasetools/build_image.py
+++ b/tools/releasetools/build_image.py
@@ -75,8 +75,8 @@
   """
   cmd = ["find", path, "-print"]
   output = common.RunAndCheckOutput(cmd, verbose=False)
-  # increase by 25 % as number of files and directories is not whole picture.
-  return output.count('\n') * 30 // 24
+  # TODO(b/122328872) Fix estimation algorithm to not need the multiplier.
+  return output.count('\n') * 2
 
 
 def GetFilesystemCharacteristics(sparse_image_path):
diff --git a/tools/releasetools/build_super_image.py b/tools/releasetools/build_super_image.py
index e8730ae..bb0e641 100755
--- a/tools/releasetools/build_super_image.py
+++ b/tools/releasetools/build_super_image.py
@@ -67,6 +67,17 @@
     return os.path.getsize(img)
 
 
+def GetArgumentsForImage(partition, group, image=None):
+  image_size = GetPartitionSizeFromImage(image) if image else 0
+
+  cmd = ["--partition",
+         "{}:readonly:{}:{}".format(partition, image_size, group)]
+  if image:
+    cmd += ["--image", "{}={}".format(partition, image)]
+
+  return cmd
+
+
 def BuildSuperImageFromDict(info_dict, output):
 
   cmd = [info_dict["lpmake"],
@@ -105,26 +116,25 @@
 
     for partition in partition_list:
       image = info_dict.get("{}_image".format(partition))
-      image_size = 0
       if image:
-        image_size = GetPartitionSizeFromImage(image)
         has_image = True
-      if append_suffix:
-        cmd += ["--partition",
-                "{}_a:readonly:{}:{}_a".format(partition, image_size, group),
-                "--partition",
-                "{}_b:readonly:0:{}_b".format(partition, group)]
-        if image:
-          # For A/B devices, super partition always contains sub-partitions in
-          # the _a slot, because this image should only be used for
-          # bootstrapping / initializing the device. When flashing the image,
-          # bootloader fastboot should always mark _a slot as bootable.
-          cmd += ["--image", "{}_a={}".format(partition, image)]
-      else:
-        cmd += ["--partition",
-                "{}:readonly:{}:{}".format(partition, image_size, group)]
-        if image:
-          cmd += ["--image", "{}={}".format(partition, image)]
+
+      if not append_suffix:
+        cmd += GetArgumentsForImage(partition, group, image)
+        continue
+
+      # For A/B devices, super partition always contains sub-partitions in
+      # the _a slot, because this image should only be used for
+      # bootstrapping / initializing the device. When flashing the image,
+      # bootloader fastboot should always mark _a slot as bootable.
+      cmd += GetArgumentsForImage(partition + "_a", group + "_a", image)
+
+      other_image = None
+      if partition == "system" and "system_other_image" in info_dict:
+        other_image = info_dict["system_other_image"]
+        has_image = True
+
+      cmd += GetArgumentsForImage(partition + "_b", group + "_b", other_image)
 
   if has_image:
     cmd.append("--sparse")
@@ -145,6 +155,12 @@
   info_dict = common.LoadInfoDict(inp)
   partition_list = shlex.split(
       info_dict.get("dynamic_partition_list", "").strip())
+
+  if "system" in partition_list:
+    image_path = os.path.join(inp, "IMAGES", "system_other.img")
+    if os.path.isfile(image_path):
+      info_dict["system_other_image"] = image_path
+
   missing_images = []
   for partition in partition_list:
     image_path = os.path.join(inp, "IMAGES", "{}.img".format(partition))
diff --git a/tools/releasetools/test_blockimgdiff.py b/tools/releasetools/test_blockimgdiff.py
index 857026e..806ff4b 100644
--- a/tools/releasetools/test_blockimgdiff.py
+++ b/tools/releasetools/test_blockimgdiff.py
@@ -127,11 +127,11 @@
 
     # Sufficient cache to stash 5 blocks (size * 0.8 >= 5).
     common.OPTIONS.cache_size = 7 * 4096
-    self.assertEqual(0, block_image_diff.ReviseStashSize())
+    self.assertEqual((0, 5), block_image_diff.ReviseStashSize())
 
     # Insufficient cache to stash 5 blocks (size * 0.8 < 5).
     common.OPTIONS.cache_size = 6 * 4096
-    self.assertEqual(10, block_image_diff.ReviseStashSize())
+    self.assertEqual((10, 0), block_image_diff.ReviseStashSize())
 
   def test_ReviseStashSize_bug_33687949(self):
     """ReviseStashSize() should "free" the used stash _after_ the command.
@@ -169,7 +169,7 @@
 
     # Insufficient cache to stash 15 blocks (size * 0.8 < 15).
     common.OPTIONS.cache_size = 15 * 4096
-    self.assertEqual(15, block_image_diff.ReviseStashSize())
+    self.assertEqual((15, 5), block_image_diff.ReviseStashSize())
 
   def test_FileTypeSupportedByImgdiff(self):
     self.assertTrue(
diff --git a/tools/signapk/Android.bp b/tools/signapk/Android.bp
index e95205d..ad9d957 100644
--- a/tools/signapk/Android.bp
+++ b/tools/signapk/Android.bp
@@ -28,4 +28,10 @@
     ],
 
     required: ["libconscrypt_openjdk_jni"],
+
+    // The post-build signing tools need signapk.jar (and its shared libraries,
+    // handled in their own Android.bp files)
+    dist: {
+        targets: ["droidcore"],
+    },
 }
diff --git a/tools/signapk/Android.mk b/tools/signapk/Android.mk
deleted file mode 100644
index ff54d6d..0000000
--- a/tools/signapk/Android.mk
+++ /dev/null
@@ -1,26 +0,0 @@
-#
-# Copyright (C) 2008 The Android Open Source Project
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#      http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-#
-LOCAL_PATH := $(call my-dir)
-
-ifeq ($(TARGET_BUILD_APPS),)
-# The post-build signing tools need signapk.jar and its shared libraries,
-# but we don't need this if we're just doing unbundled apps.
-my_dist_files := $(HOST_OUT_JAVA_LIBRARIES)/signapk.jar \
-    $(HOST_OUT_SHARED_LIBRARIES)/libconscrypt_openjdk_jni$(HOST_SHLIB_SUFFIX)
-
-$(call dist-for-goals,droidcore,$(my_dist_files))
-my_dist_files :=
-endif