diff --git a/core/Makefile b/core/Makefile
index d39f9de..03d4b03 100644
--- a/core/Makefile
+++ b/core/Makefile
@@ -418,7 +418,7 @@
 $(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) $(POST_PROCESS_PROPS)
 	@echo Target buildinfo: $@
 	@mkdir -p $(dir $@)
-	$(hide) echo > $@
+	$(hide) touch $@
 ifneq ($(PRODUCT_OEM_PROPERTIES),)
 	$(hide) echo "#" >> $@; \
 	        echo "# PRODUCT_OEM_PROPERTIES" >> $@; \
@@ -517,7 +517,7 @@
 $(INSTALLED_VENDOR_BUILD_PROP_TARGET): $(BUILDINFO_COMMON_SH) $(POST_PROCESS_PROPS) $(intermediate_system_build_prop) $(vendor_prop_files)
 	@echo Target vendor buildinfo: $@
 	@mkdir -p $(dir $@)
-	$(hide) echo > $@
+	$(hide) touch $@
 ifeq ($(PRODUCT_USE_DYNAMIC_PARTITIONS),true)
 	$(hide) echo ro.boot.dynamic_partitions=true >> $@
 endif
@@ -584,7 +584,7 @@
 $(INSTALLED_PRODUCT_BUILD_PROP_TARGET): $(BUILDINFO_COMMON_SH) $(POST_PROCESS_PROPS) $(product_prop_files)
 	@echo Target product buildinfo: $@
 	@mkdir -p $(dir $@)
-	$(hide) echo > $@
+	$(hide) touch $@
 ifdef BOARD_USES_PRODUCTIMAGE
 	$(hide) $(call generate-common-build-props,product,$@)
 endif  # BOARD_USES_PRODUCTIMAGE
@@ -625,7 +625,7 @@
 $(INSTALLED_ODM_BUILD_PROP_TARGET): $(BUILDINFO_COMMON_SH) $(POST_PROCESS_PROPS) $(odm_prop_files)
 	@echo Target odm buildinfo: $@
 	@mkdir -p $(dir $@)
-	$(hide) echo > $@
+	$(hide) touch $@
 	$(hide) echo ro.odm.product.cpu.abilist="$(TARGET_CPU_ABI_LIST)">>$@
 	$(hide) echo ro.odm.product.cpu.abilist32="$(TARGET_CPU_ABI_LIST_32_BIT)">>$@
 	$(hide) echo ro.odm.product.cpu.abilist64="$(TARGET_CPU_ABI_LIST_64_BIT)">>$@
@@ -666,7 +666,7 @@
 $(INSTALLED_SYSTEM_EXT_BUILD_PROP_TARGET): $(BUILDINFO_COMMON_SH) $(POST_PROCESS_PROPS) $(system_ext_prop_files)
 	@echo Target system_ext buildinfo: $@
 	@mkdir -p $(dir $@)
-	$(hide) echo > $@
+	$(hide) touch $@
 	$(hide) $(call generate-common-build-props,system_ext,$@)
 	$(hide) $(foreach file,$(system_ext_prop_files), \
 	    if [ -f "$(file)" ]; then \
@@ -1032,7 +1032,12 @@
   INSTALLED_2NDBOOTLOADER_TARGET :=
 endif # TARGET_NO_BOOTLOADER
 ifneq ($(strip $(TARGET_NO_KERNEL)),true)
-  INSTALLED_KERNEL_TARGET := $(PRODUCT_OUT)/kernel
+  ifneq ($(strip $(BOARD_KERNEL_BINARIES)),)
+    INSTALLED_KERNEL_TARGET := $(foreach k,$(BOARD_KERNEL_BINARIES), \
+      $(PRODUCT_OUT)/$(k))
+  else
+    INSTALLED_KERNEL_TARGET := $(PRODUCT_OUT)/kernel
+  endif
 else
   INSTALLED_KERNEL_TARGET :=
 endif
@@ -1104,7 +1109,12 @@
 
 # This is defined here since we may be building recovery as boot
 # below and only want to define this once
-BUILT_BOOTIMAGE_TARGET := $(PRODUCT_OUT)/boot.img
+ifneq ($(strip $(BOARD_KERNEL_BINARIES)),)
+  BUILT_BOOTIMAGE_TARGET := $(foreach k,$(subst kernel,boot,$(BOARD_KERNEL_BINARIES)), $(PRODUCT_OUT)/$(k).img)
+else
+  BUILT_BOOTIMAGE_TARGET := $(PRODUCT_OUT)/boot.img
+endif
+
 
 ifneq ($(strip $(TARGET_NO_KERNEL)),true)
 INTERNAL_BOOTIMAGE_ARGS := \
@@ -2113,7 +2123,7 @@
 else # INSTALLED_VENDOR_BOOTIMAGE_TARGET not defined
   INTERNAL_RECOVERYIMAGE_ARGS := \
       $(addprefix --second ,$(INSTALLED_2NDBOOTLOADER_TARGET)) \
-      --kernel $(recovery_kernel) --ramdisk $(recovery_ramdisk)
+      --ramdisk $(recovery_ramdisk)
 # Assumes this has already been stripped
 ifdef INTERNAL_KERNEL_CMDLINE
   INTERNAL_RECOVERYIMAGE_ARGS += --cmdline "$(INTERNAL_KERNEL_CMDLINE)"
@@ -2139,38 +2149,53 @@
 endif
 endif # INSTALLED_VENDOR_BOOTIMAGE_TARGET not defined
 
+$(recovery_ramdisk): $(MKBOOTFS) $(MINIGZIP) \
+	    $(INTERNAL_ROOT_FILES) \
+	    $(INSTALLED_RAMDISK_TARGET) \
+	    $(INTERNAL_RECOVERYIMAGE_FILES) \
+	    $(recovery_sepolicy) \
+	    $(INSTALLED_2NDBOOTLOADER_TARGET) \
+	    $(INSTALLED_RECOVERY_BUILD_PROP_TARGET) \
+	    $(recovery_resource_deps) \
+	    $(recovery_fstab)
+	# Making recovery image
+	mkdir -p $(TARGET_RECOVERY_OUT)
+	mkdir -p $(TARGET_RECOVERY_ROOT_OUT)/sdcard $(TARGET_RECOVERY_ROOT_OUT)/tmp
+	# Copying baseline ramdisk...
+	# Use rsync because "cp -Rf" fails to overwrite broken symlinks on Mac.
+	rsync -a --exclude=sdcard $(IGNORE_RECOVERY_SEPOLICY) $(IGNORE_CACHE_LINK) $(TARGET_ROOT_OUT) $(TARGET_RECOVERY_OUT)
+	# Modifying ramdisk contents...
+	$(if $(filter true,$(BOARD_BUILD_SYSTEM_ROOT_IMAGE)),, \
+	  ln -sf /system/bin/init $(TARGET_RECOVERY_ROOT_OUT)/init)
+	# Removes $(TARGET_RECOVERY_ROOT_OUT)/init*.rc EXCEPT init.recovery*.rc.
+	find $(TARGET_RECOVERY_ROOT_OUT) -maxdepth 1 -name 'init*.rc' -type f -not -name "init.recovery.*.rc" | xargs rm -f
+	cp $(TARGET_ROOT_OUT)/init.recovery.*.rc $(TARGET_RECOVERY_ROOT_OUT)/ 2> /dev/null || true # Ignore error when the src file doesn't exist.
+	mkdir -p $(TARGET_RECOVERY_ROOT_OUT)/res
+	rm -rf $(TARGET_RECOVERY_ROOT_OUT)/res/*
+	cp -rf $(recovery_resources_common)/* $(TARGET_RECOVERY_ROOT_OUT)/res
+	$(foreach recovery_text_file,$(generated_recovery_text_files), \
+	  cp -rf $(recovery_text_file) $(TARGET_RECOVERY_ROOT_OUT)/res/images/ &&) true
+	cp -f $(recovery_font) $(TARGET_RECOVERY_ROOT_OUT)/res/images/font.png
+	$(foreach item,$(TARGET_PRIVATE_RES_DIRS), \
+	  cp -rf $(item) $(TARGET_RECOVERY_ROOT_OUT)/$(newline))
+	$(foreach item,$(recovery_fstab), \
+	  cp -f $(item) $(TARGET_RECOVERY_ROOT_OUT)/system/etc/recovery.fstab)
+	$(if $(strip $(recovery_wipe)), \
+	  cp -f $(recovery_wipe) $(TARGET_RECOVERY_ROOT_OUT)/system/etc/recovery.wipe)
+	ln -sf prop.default $(TARGET_RECOVERY_ROOT_OUT)/default.prop
+	$(BOARD_RECOVERY_IMAGE_PREPARE)
+	$(MKBOOTFS) -d $(TARGET_OUT) $(TARGET_RECOVERY_ROOT_OUT) | $(MINIGZIP) > $(recovery_ramdisk)
+
 # $(1): output file
+# $(2): kernel file
 define build-recoveryimage-target
-  # Making recovery image
-  $(hide) mkdir -p $(TARGET_RECOVERY_OUT)
-  $(hide) mkdir -p $(TARGET_RECOVERY_ROOT_OUT)/sdcard $(TARGET_RECOVERY_ROOT_OUT)/tmp
-  # Copying baseline ramdisk...
-  # Use rsync because "cp -Rf" fails to overwrite broken symlinks on Mac.
-  $(hide) rsync -a --exclude=sdcard $(IGNORE_RECOVERY_SEPOLICY) $(IGNORE_CACHE_LINK) $(TARGET_ROOT_OUT) $(TARGET_RECOVERY_OUT)
-  # Modifying ramdisk contents...
-  $(if $(filter true,$(BOARD_BUILD_SYSTEM_ROOT_IMAGE)),, \
-    $(hide) ln -sf /system/bin/init $(TARGET_RECOVERY_ROOT_OUT)/init)
-  # Removes $(TARGET_RECOVERY_ROOT_OUT)/init*.rc EXCEPT init.recovery*.rc.
-  $(hide) find $(TARGET_RECOVERY_ROOT_OUT) -maxdepth 1 -name 'init*.rc' -type f -not -name "init.recovery.*.rc" | xargs rm -f
-  $(hide) cp $(TARGET_ROOT_OUT)/init.recovery.*.rc $(TARGET_RECOVERY_ROOT_OUT)/ 2> /dev/null || true # Ignore error when the src file doesn't exist.
-  $(hide) mkdir -p $(TARGET_RECOVERY_ROOT_OUT)/res
-  $(hide) rm -rf $(TARGET_RECOVERY_ROOT_OUT)/res/*
-  $(hide) cp -rf $(recovery_resources_common)/* $(TARGET_RECOVERY_ROOT_OUT)/res
-  $(hide) $(foreach recovery_text_file,$(generated_recovery_text_files), \
-    cp -rf $(recovery_text_file) $(TARGET_RECOVERY_ROOT_OUT)/res/images/ &&) true
-  $(hide) cp -f $(recovery_font) $(TARGET_RECOVERY_ROOT_OUT)/res/images/font.png
-  $(hide) $(foreach item,$(TARGET_PRIVATE_RES_DIRS), \
-    cp -rf $(item) $(TARGET_RECOVERY_ROOT_OUT)/$(newline))
-  $(hide) $(foreach item,$(recovery_fstab), \
-    cp -f $(item) $(TARGET_RECOVERY_ROOT_OUT)/system/etc/recovery.fstab)
-  $(if $(strip $(recovery_wipe)), \
-    $(hide) cp -f $(recovery_wipe) $(TARGET_RECOVERY_ROOT_OUT)/system/etc/recovery.wipe)
-  $(hide) ln -sf prop.default $(TARGET_RECOVERY_ROOT_OUT)/default.prop
-  $(BOARD_RECOVERY_IMAGE_PREPARE)
-  $(hide) $(MKBOOTFS) -d $(TARGET_OUT) $(TARGET_RECOVERY_ROOT_OUT) | $(MINIGZIP) > $(recovery_ramdisk)
   $(if $(filter true,$(PRODUCT_SUPPORTS_VBOOT)), \
-    $(hide) $(MKBOOTIMG) $(INTERNAL_RECOVERYIMAGE_ARGS) $(INTERNAL_MKBOOTIMG_VERSION_ARGS) $(BOARD_MKBOOTIMG_ARGS) --output $(1).unsigned, \
-    $(hide) $(MKBOOTIMG) $(INTERNAL_RECOVERYIMAGE_ARGS) $(INTERNAL_MKBOOTIMG_VERSION_ARGS) $(BOARD_MKBOOTIMG_ARGS) --output $(1))
+    $(MKBOOTIMG) --kernel $(2) $(MKBOOTIMG_KERNEL_ARG) $(INTERNAL_RECOVERYIMAGE_ARGS) \
+                 $(INTERNAL_MKBOOTIMG_VERSION_ARGS) $(BOARD_MKBOOTIMG_ARGS) \
+                 --output $(1).unsigned, \
+    $(MKBOOTIMG) --kernel $(2) $(MKBOOTIMG_KERNEL_ARG) $(INTERNAL_RECOVERYIMAGE_ARGS) \
+                 $(INTERNAL_MKBOOTIMG_VERSION_ARGS) $(BOARD_MKBOOTIMG_ARGS) \
+                 --output $(1))
   $(if $(filter true,$(PRODUCT_SUPPORTS_BOOT_SIGNER)),\
     $(if $(filter true,$(BOARD_USES_RECOVERY_AS_BOOT)),\
       $(BOOT_SIGNER) /boot $(1) $(PRODUCT_VERITY_SIGNING_KEY).pk8 $(PRODUCT_VERITY_SIGNING_KEY).x509.pem $(1),\
@@ -2180,12 +2205,12 @@
   $(if $(filter true,$(PRODUCT_SUPPORTS_VBOOT)), \
     $(VBOOT_SIGNER) $(FUTILITY) $(1).unsigned $(PRODUCT_VBOOT_SIGNING_KEY).vbpubk $(PRODUCT_VBOOT_SIGNING_KEY).vbprivk $(PRODUCT_VBOOT_SIGNING_SUBKEY).vbprivk $(1).keyblock $(1))
   $(if $(filter true,$(BOARD_USES_RECOVERY_AS_BOOT)), \
-    $(hide) $(call assert-max-image-size,$(1),$(call get-hash-image-max-size,$(BOARD_BOOTIMAGE_PARTITION_SIZE))), \
-    $(hide) $(call assert-max-image-size,$(1),$(call get-hash-image-max-size,$(BOARD_RECOVERYIMAGE_PARTITION_SIZE))))
+    $(call assert-max-image-size,$(1),$(call get-hash-image-max-size,$(BOARD_BOOTIMAGE_PARTITION_SIZE))), \
+    $(call assert-max-image-size,$(1),$(call get-hash-image-max-size,$(BOARD_RECOVERYIMAGE_PARTITION_SIZE))))
   $(if $(filter true,$(BOARD_AVB_ENABLE)), \
     $(if $(filter true,$(BOARD_USES_RECOVERY_AS_BOOT)), \
-      $(hide) $(AVBTOOL) add_hash_footer --image $(1) --partition_size $(BOARD_BOOTIMAGE_PARTITION_SIZE) --partition_name boot $(INTERNAL_AVB_BOOT_SIGNING_ARGS) $(BOARD_AVB_BOOT_ADD_HASH_FOOTER_ARGS),\
-      $(hide) $(AVBTOOL) add_hash_footer --image $(1) --partition_size $(BOARD_RECOVERYIMAGE_PARTITION_SIZE) --partition_name recovery $(INTERNAL_AVB_RECOVERY_SIGNING_ARGS) $(BOARD_AVB_RECOVERY_ADD_HASH_FOOTER_ARGS)))
+      $(AVBTOOL) add_hash_footer --image $(1) --partition_size $(BOARD_BOOTIMAGE_PARTITION_SIZE) --partition_name boot $(INTERNAL_AVB_BOOT_SIGNING_ARGS) $(BOARD_AVB_BOOT_ADD_HASH_FOOTER_ARGS),\
+      $(AVBTOOL) add_hash_footer --image $(1) --partition_size $(BOARD_RECOVERYIMAGE_PARTITION_SIZE) --partition_name recovery $(INTERNAL_AVB_RECOVERY_SIGNING_ARGS) $(BOARD_AVB_RECOVERY_ADD_HASH_FOOTER_ARGS)))
 endef
 
 ifeq ($(BOARD_USES_RECOVERY_AS_BOOT),true)
@@ -2212,18 +2237,10 @@
 $(INSTALLED_BOOTIMAGE_TARGET): $(INSTALLED_DTBIMAGE_TARGET)
 endif
 
-$(INSTALLED_BOOTIMAGE_TARGET): $(MKBOOTFS) $(MKBOOTIMG) $(MINIGZIP) \
-	    $(INTERNAL_ROOT_FILES) \
-	    $(INSTALLED_RAMDISK_TARGET) \
-	    $(INTERNAL_RECOVERYIMAGE_FILES) \
-	    $(recovery_sepolicy) $(recovery_kernel) \
-	    $(INSTALLED_2NDBOOTLOADER_TARGET) \
-	    $(INSTALLED_RECOVERY_BUILD_PROP_TARGET) \
-	    $(recovery_resource_deps) \
-	    $(recovery_fstab)
+$(INSTALLED_BOOTIMAGE_TARGET): $(MKBOOTIMG) $(recovery_ramdisk) \
+	    $(recovery_kernel)
 	$(call pretty,"Target boot image from recovery: $@")
-	$(call build-recoveryimage-target, $@)
-$(INSTALLED_BOOTIMAGE_TARGET): .KATI_IMPLICIT_OUTPUTS += $(recovery_ramdisk)
+	$(call build-recoveryimage-target, $@, $(PRODUCT_OUT)/$(subst .img,,$(subst boot,kernel,$(notdir $@))))
 endif # BOARD_USES_RECOVERY_AS_BOOT
 
 ifdef BOARD_INCLUDE_RECOVERY_DTBO
@@ -2240,17 +2257,9 @@
 $(INSTALLED_RECOVERYIMAGE_TARGET): $(INSTALLED_DTBIMAGE_TARGET)
 endif
 
-$(INSTALLED_RECOVERYIMAGE_TARGET): $(MKBOOTFS) $(MKBOOTIMG) $(MINIGZIP) \
-	    $(INTERNAL_ROOT_FILES) \
-	    $(INSTALLED_RAMDISK_TARGET) \
-	    $(INSTALLED_BOOTIMAGE_TARGET) \
-	    $(INTERNAL_RECOVERYIMAGE_FILES) \
-	    $(recovery_sepolicy) $(recovery_kernel) \
-	    $(INSTALLED_2NDBOOTLOADER_TARGET) \
-	    $(INSTALLED_RECOVERY_BUILD_PROP_TARGET) \
-	    $(recovery_resource_deps) \
-	    $(recovery_fstab)
-	$(call build-recoveryimage-target, $@)
+$(INSTALLED_RECOVERYIMAGE_TARGET): $(MKBOOTIMG) $(recovery_ramdisk) \
+	    $(recovery_kernel)
+	$(call build-recoveryimage-target, $@, $(recovery_kernel))
 
 ifdef RECOVERY_RESOURCE_ZIP
 $(RECOVERY_RESOURCE_ZIP): $(INSTALLED_RECOVERYIMAGE_TARGET) | $(ZIPTIME)
@@ -2361,8 +2370,12 @@
 # Note: it's intentional to skip signing for boot-debug.img, because it
 # can only be used if the device is unlocked with verification error.
 ifneq ($(strip $(TARGET_NO_KERNEL)),true)
-
-INSTALLED_DEBUG_BOOTIMAGE_TARGET := $(PRODUCT_OUT)/boot-debug.img
+ifneq ($(strip $(BOARD_KERNEL_BINARIES)),)
+  INSTALLED_DEBUG_BOOTIMAGE_TARGET := $(foreach k,$(subst kernel,boot-debug,$(BOARD_KERNEL_BINARIES)), \
+         $(PRODUCT_OUT)/$(k).img)
+else
+  INSTALLED_DEBUG_BOOTIMAGE_TARGET := $(PRODUCT_OUT)/boot-debug.img
+endif
 
 # Replace ramdisk.img in $(MKBOOTIMG) ARGS with ramdisk-debug.img to build boot-debug.img
 ifeq ($(BOARD_USES_RECOVERY_AS_BOOT),true)
@@ -2392,17 +2405,22 @@
 $(call assert-max-image-size,$(1),$(BOARD_BOOTIMAGE_PARTITION_SIZE))
 endef
 
+# $(1): output file
+define build-debug-bootimage-target
+  $(MKBOOTIMG) --kernel $(PRODUCT_OUT)/$(subst .img,,$(subst boot-debug,kernel,$(notdir $(1)))) \
+    $(INTERNAL_DEBUG_BOOTIMAGE_ARGS) $(INTERNAL_MKBOOTIMG_VERSION_ARGS) $(BOARD_MKBOOTIMG_ARGS) --output $1
+  $(if $(BOARD_AVB_BOOT_KEY_PATH),$(call test-key-sign-bootimage,$1))
+endef
+
 # Depends on original boot.img and ramdisk-debug.img, to build the new boot-debug.img
 $(INSTALLED_DEBUG_BOOTIMAGE_TARGET): $(MKBOOTIMG) $(INSTALLED_BOOTIMAGE_TARGET) $(INSTALLED_DEBUG_RAMDISK_TARGET)
 	$(call pretty,"Target boot debug image: $@")
-	$(MKBOOTIMG) $(INTERNAL_DEBUG_BOOTIMAGE_ARGS) $(INTERNAL_MKBOOTIMG_VERSION_ARGS) $(BOARD_MKBOOTIMG_ARGS) --output $@
-	$(if $(BOARD_AVB_BOOT_KEY_PATH),$(call test-key-sign-bootimage,$@))
+	$(call build-debug-bootimage-target, $@)
 
 .PHONY: bootimage_debug-nodeps
 bootimage_debug-nodeps: $(MKBOOTIMG)
 	echo "make $@: ignoring dependencies"
-	$(MKBOOTIMG) $(INTERNAL_DEBUG_BOOTIMAGE_ARGS) $(INTERNAL_MKBOOTIMG_VERSION_ARGS) $(BOARD_MKBOOTIMG_ARGS) --output $(INSTALLED_DEBUG_BOOTIMAGE_TARGET)
-	$(if $(BOARD_AVB_BOOT_KEY_PATH),$(call test-key-sign-bootimage,$(INSTALLED_DEBUG_BOOTIMAGE_TARGET)))
+	$(foreach b,$(INSTALLED_DEBUG_BOOTIMAGE_TARGET),$(call build-debug-bootimage-target,$b))
 
 endif # TARGET_NO_KERNEL
 
@@ -3697,6 +3715,13 @@
 check_vintf_has_system :=
 check_vintf_has_vendor :=
 
+ifneq (,$(filter EMPTY_ODM_SKU_PLACEHOLDER,$(ODM_MANIFEST_SKUS)))
+$(error EMPTY_ODM_SKU_PLACEHOLDER is an internal variable and cannot be used for ODM_MANIFEST_SKUS)
+endif
+ifneq (,$(filter EMPTY_VENDOR_SKU_PLACEHOLDER,$(DEVICE_MANIFEST_SKUS)))
+$(error EMPTY_VENDOR_SKU_PLACEHOLDER is an internal variable and cannot be used for DEIVCE_MANIFEST_SKUS)
+endif
+
 # -- Check system manifest / matrix including fragments (excluding other framework manifests / matrices, e.g. product);
 check_vintf_system_deps := $(filter $(TARGET_OUT)/etc/vintf/%, $(check_vintf_common_srcs))
 ifneq ($(check_vintf_system_deps),)
@@ -3715,8 +3740,18 @@
 check_vintf_has_vendor := true
 check_vintf_vendor_log := $(intermediates)/check_vintf_vendor_log
 check_vintf_all_deps += $(check_vintf_vendor_log)
+# Check vendor SKU=(empty) case when:
+# - DEVICE_MANIFEST_FILE is not empty; OR
+# - DEVICE_MANIFEST_FILE is empty AND DEVICE_MANIFEST_SKUS is empty (only vendor manifest fragments are used)
+$(check_vintf_vendor_log): PRIVATE_VENDOR_SKUS := \
+  $(if $(DEVICE_MANIFEST_FILE),EMPTY_VENDOR_SKU_PLACEHOLDER,\
+    $(if $(DEVICE_MANIFEST_SKUS),,EMPTY_VENDOR_SKU_PLACEHOLDER)) \
+  $(DEVICE_MANIFEST_SKUS)
 $(check_vintf_vendor_log): $(HOST_OUT_EXECUTABLES)/checkvintf $(check_vintf_vendor_deps)
-	@( $< --check-one --dirmap /vendor:$(TARGET_OUT_VENDOR) > $@ 2>&1 ) || ( cat $@ && exit 1 )
+	$(foreach vendor_sku,$(PRIVATE_VENDOR_SKUS), \
+	  ( $< --check-one --dirmap /vendor:$(TARGET_OUT_VENDOR) \
+	       --property ro.boot.product.vendor.sku=$(filter-out EMPTY_VENDOR_SKU_PLACEHOLDER,$(vendor_sku)) \
+	       > $@ 2>&1 ) || ( cat $@ && exit 1 ); )
 check_vintf_vendor_log :=
 endif # check_vintf_vendor_deps
 check_vintf_vendor_deps :=
@@ -3810,17 +3845,31 @@
 
 $(check_vintf_compatible_log): PRIVATE_CHECK_VINTF_ARGS := $(check_vintf_compatible_args)
 $(check_vintf_compatible_log): PRIVATE_CHECK_VINTF_DEPS := $(check_vintf_compatible_deps)
+# Check ODM SKU=(empty) case when:
+# - ODM_MANIFEST_FILES is not empty; OR
+# - ODM_MANIFEST_FILES is empty AND ODM_MANIFEST_SKUS is empty (only ODM manifest fragments are used)
+$(check_vintf_compatible_log): PRIVATE_ODM_SKUS := \
+  $(if $(ODM_MANIFEST_FILES),EMPTY_ODM_SKU_PLACEHOLDER,\
+    $(if $(ODM_MANIFEST_SKUS),,EMPTY_ODM_SKU_PLACEHOLDER)) \
+  $(ODM_MANIFEST_SKUS)
+# Check vendor SKU=(empty) case when:
+# - DEVICE_MANIFEST_FILE is not empty; OR
+# - DEVICE_MANIFEST_FILE is empty AND DEVICE_MANIFEST_SKUS is empty (only vendor manifest fragments are used)
+$(check_vintf_compatible_log): PRIVATE_VENDOR_SKUS := \
+  $(if $(DEVICE_MANIFEST_FILE),EMPTY_VENDOR_SKU_PLACEHOLDER,\
+    $(if $(DEVICE_MANIFEST_SKUS),,EMPTY_VENDOR_SKU_PLACEHOLDER)) \
+  $(DEVICE_MANIFEST_SKUS)
 $(check_vintf_compatible_log): $(HOST_OUT_EXECUTABLES)/checkvintf $(check_vintf_compatible_deps)
 	@echo -n -e 'Deps: \n  ' > $@
 	@sed 's/ /\n  /g' <<< "$(PRIVATE_CHECK_VINTF_DEPS)" >> $@
 	@echo -n -e 'Args: \n  ' >> $@
 	@cat <<< "$(PRIVATE_CHECK_VINTF_ARGS)" >> $@
-	@echo -n -e 'For empty SKU:' >> $@
-	@( $< --check-compat $(PRIVATE_CHECK_VINTF_ARGS) >> $@ 2>&1 ) || ( cat $@ && exit 1 )
-	$(foreach sku,$(ODM_MANIFEST_SKUS), \
-	  echo "For SKU = $(sku):" >> $@; \
+	$(foreach odm_sku,$(PRIVATE_ODM_SKUS), $(foreach vendor_sku,$(PRIVATE_VENDOR_SKUS), \
+	  echo "For ODM SKU = $(odm_sku), vendor SKU = $(vendor_sku)" >> $@; \
 	  ( $< --check-compat $(PRIVATE_CHECK_VINTF_ARGS) \
-	      --property ro.boot.product.hardware.sku=$(sku) >> $@ 2>&1 ) || ( cat $@ && exit 1 ); )
+	       --property ro.boot.product.hardware.sku=$(filter-out EMPTY_ODM_SKU_PLACEHOLDER,$(odm_sku)) \
+	       --property ro.boot.product.vendor.sku=$(filter-out EMPTY_VENDOR_SKU_PLACEHOLDER,$(vendor_sku)) \
+	       >> $@ 2>&1 ) || (cat $@ && exit 1); ))
 
 check_vintf_compatible_log :=
 check_vintf_compatible_args :=
@@ -4219,6 +4268,15 @@
 ifdef ODM_MANIFEST_SKUS
 	$(hide) echo "vintf_odm_manifest_skus=$(ODM_MANIFEST_SKUS)" >> $@
 endif
+ifdef ODM_MANIFEST_FILES
+	$(hide) echo "vintf_include_empty_odm_sku=true" >> $@
+endif
+ifdef DEVICE_MANIFEST_SKUS
+	$(hide) echo "vintf_vendor_manifest_skus=$(DEVICE_MANIFEST_SKUS)" >> $@
+endif
+ifdef DEVICE_MANIFEST_FILE
+	$(hide) echo "vintf_include_empty_vendor_sku=true" >> $@
+endif
 
 .PHONY: misc_info
 misc_info: $(INSTALLED_MISC_INFO_TARGET)
@@ -4426,7 +4484,7 @@
 	$(hide) $(call package_files-copy-root, \
 	    $(TARGET_RECOVERY_ROOT_OUT),$(zip_root)/$(PRIVATE_RECOVERY_OUT)/RAMDISK)
 ifdef INSTALLED_KERNEL_TARGET
-	cp $(INSTALLED_KERNEL_TARGET) $(zip_root)/$(PRIVATE_RECOVERY_OUT)/kernel
+	cp $(INSTALLED_KERNEL_TARGET) $(zip_root)/$(PRIVATE_RECOVERY_OUT)/
 endif
 ifdef INSTALLED_VENDOR_BOOTIMAGE_TARGET
 	echo "$(GENERIC_KERNEL_CMDLINE)" > $(zip_root)/$(PRIVATE_RECOVERY_OUT)/cmdline
@@ -5198,7 +5256,6 @@
 	$(ALL_DEFAULT_INSTALLED_MODULES) \
 	$(INSTALLED_RAMDISK_TARGET) \
 	$(ALL_DOCS) \
-	$(TARGET_OUT_COMMON_INTERMEDIATES)/PACKAGING/api-stubs-docs_annotations.zip \
 	$(ALL_SDK_FILES)
 endif
 
diff --git a/core/base_rules.mk b/core/base_rules.mk
index cce6ec1..f70911e 100644
--- a/core/base_rules.mk
+++ b/core/base_rules.mk
@@ -705,13 +705,19 @@
 
 ifeq ($(use_testcase_folder),true)
 ifneq ($(my_test_data_file_pairs),)
+# Filter out existng installed test data paths when collecting test data files to be installed and
+# indexed as they cause build rule conflicts. Instead put them in a separate list which is only
+# used for indexing.
 $(foreach pair, $(my_test_data_file_pairs), \
   $(eval parts := $(subst :,$(space),$(pair))) \
   $(eval src_path := $(word 1,$(parts))) \
   $(eval file := $(word 2,$(parts))) \
   $(foreach suite, $(LOCAL_COMPATIBILITY_SUITE), \
     $(eval my_compat_dist_$(suite) += $(foreach dir, $(call compatibility_suite_dirs,$(suite),$(arch_dir)), \
-      $(call filter-copy-pair,$(src_path),$(call append-path,$(dir),$(file)),$(my_installed_test_data))))))
+      $(call filter-copy-pair,$(src_path),$(call append-path,$(dir),$(file)),$(my_installed_test_data)))) \
+    $(eval my_compat_dist_test_data_$(suite) += \
+      $(foreach dir, $(call compatibility_suite_dirs,$(suite),$(arch_dir)), \
+        $(filter $(my_installed_test_data),$(call append-path,$(dir),$(file)))))))
 endif
 else
 ifneq ($(my_test_data_file_pairs),)
@@ -732,7 +738,8 @@
 
 $(call create-suite-dependencies)
 $(foreach suite, $(LOCAL_COMPATIBILITY_SUITE), \
-  $(eval my_compat_dist_config_$(suite) := ))
+  $(eval my_compat_dist_config_$(suite) := ) \
+  $(eval my_compat_dist_test_data_$(suite) := ))
 
 endif  # LOCAL_COMPATIBILITY_SUITE
 
diff --git a/core/definitions.mk b/core/definitions.mk
index fb11ab6..3499da9 100644
--- a/core/definitions.mk
+++ b/core/definitions.mk
@@ -2897,7 +2897,8 @@
   $(if $(filter $(suite),$(ALL_COMPATIBILITY_SUITES)),,$(eval ALL_COMPATIBILITY_SUITES += $(suite))) \
   $(eval COMPATIBILITY.$(suite).FILES := \
     $$(COMPATIBILITY.$(suite).FILES) $$(foreach f,$$(my_compat_dist_$(suite)),$$(call word-colon,2,$$(f))) \
-      $$(foreach f,$$(my_compat_dist_config_$(suite)),$$(call word-colon,2,$$(f)))) \
+      $$(foreach f,$$(my_compat_dist_config_$(suite)),$$(call word-colon,2,$$(f))) \
+      $$(my_compat_dist_test_data_$(suite))) \
   $(eval COMPATIBILITY.$(suite).MODULES := \
     $$(COMPATIBILITY.$(suite).MODULES) $$(my_register_name))) \
 $(eval $(my_all_targets) : $(call copy-many-files, \
diff --git a/core/dex_preopt.mk b/core/dex_preopt.mk
index 55eeec6..20b4051 100644
--- a/core/dex_preopt.mk
+++ b/core/dex_preopt.mk
@@ -18,9 +18,35 @@
 ALL_DEFAULT_INSTALLED_MODULES += $(call copy-many-files,$(DEXPREOPT_IMAGE_PROFILE_BUILT_INSTALLED),$(PRODUCT_OUT))
 
 # Install boot images. Note that there can be multiple.
+my_boot_image_arch := TARGET_ARCH
+my_boot_image_out := $(PRODUCT_OUT)
+my_boot_image_syms := $(TARGET_OUT_UNSTRIPPED)
+my_boot_image_root := DEFAULT_DEX_PREOPT_INSTALLED_IMAGE
 DEFAULT_DEX_PREOPT_INSTALLED_IMAGE :=
-$(TARGET_2ND_ARCH_VAR_PREFIX)DEFAULT_DEX_PREOPT_INSTALLED_IMAGE :=
 $(foreach my_boot_image_name,$(DEXPREOPT_IMAGE_NAMES),$(eval include $(BUILD_SYSTEM)/dex_preopt_libart.mk))
+ifdef TARGET_2ND_ARCH
+  my_boot_image_arch := TARGET_2ND_ARCH
+  my_boot_image_root := 2ND_DEFAULT_DEX_PREOPT_INSTALLED_IMAGE
+  2ND_DEFAULT_DEX_PREOPT_INSTALLED_IMAGE :=
+  $(foreach my_boot_image_name,$(DEXPREOPT_IMAGE_NAMES),$(eval include $(BUILD_SYSTEM)/dex_preopt_libart.mk))
+endif
+# Install boot images for testing on host. We exclude framework image as it is not part of art manifest.
+my_boot_image_arch := HOST_ARCH
+my_boot_image_out := $(HOST_OUT)
+my_boot_image_syms := $(HOST_OUT)/symbols
+my_boot_image_root := HOST_BOOT_IMAGE
+HOST_BOOT_IMAGE :=
+$(foreach my_boot_image_name,art_host,$(eval include $(BUILD_SYSTEM)/dex_preopt_libart.mk))
+ifdef HOST_2ND_ARCH
+  my_boot_image_arch := HOST_2ND_ARCH
+  my_boot_image_root := 2ND_HOST_BOOT_IMAGE
+  2ND_HOST_BOOT_IMAGE :=
+  $(foreach my_boot_image_name,art_host,$(eval include $(BUILD_SYSTEM)/dex_preopt_libart.mk))
+endif
+my_boot_image_arch :=
+my_boot_image_out :=
+my_boot_image_syms :=
+my_boot_image_root :=
 
 # Build the boot.zip which contains the boot jars and their compilation output
 # We can do this only if preopt is enabled and if the product uses libart config (which sets the
diff --git a/core/dex_preopt_libart.mk b/core/dex_preopt_libart.mk
index 79d5f8c..12b29f4 100644
--- a/core/dex_preopt_libart.mk
+++ b/core/dex_preopt_libart.mk
@@ -1,45 +1,42 @@
 ####################################
 # ART boot image installation
-# Input variable:
+# Input variables:
 #   my_boot_image_name: the boot image to install
+#   my_boot_image_arch: the architecture to install (e.g. TARGET_ARCH, not expanded)
+#   my_boot_image_out:  the install directory (e.g. $(PRODUCT_OUT))
+#   my_boot_image_syms: the symbols director (e.g. $(TARGET_OUT_UNSTRIPPED))
+#   my_boot_image_root: make variable used to store installed image path
 #
 ####################################
 
-# Install primary arch vdex files into a shared location, and then symlink them to both the primary
-# and secondary arch directories.
-my_vdex_copy_pairs := $(DEXPREOPT_IMAGE_VDEX_BUILT_INSTALLED_$(my_boot_image_name)_$(TARGET_ARCH))
-my_installed := $(foreach v,$(my_vdex_copy_pairs),$(PRODUCT_OUT)$(call word-colon,2,$(v)))
+# Install $(1) to $(2) so that it is shared between architectures.
+define copy-vdex-file
+my_vdex_shared := $$(dir $$(patsubst %/,%,$$(dir $(2))))$$(notdir $(2))  # Remove the arch dir.
+ifneq ($(my_boot_image_arch),$(filter $(my_boot_image_arch), TARGET_2ND_ARCH HOST_2ND_ARCH))
+$$(my_vdex_shared): $(1)  # Copy $(1) to directory one level up (i.e. with the arch dir removed).
+	@echo "Install: $$@"
+	$$(copy-file-to-target)
+endif
+$(2): $$(my_vdex_shared)  # Create symlink at $(2) which points to the actual physical copy.
+	@echo "Symlink: $$@"
+	mkdir -p $$(dir $$@)
+	ln -sfn ../$$(notdir $$@) $$@
+my_vdex_shared :=
+endef
+
+# Same as 'copy-many-files' but it uses the vdex-specific helper above.
+define copy-vdex-files
+$(foreach v,$(1),$(eval $(call copy-vdex-file, $(call word-colon,1,$(v)), $(2)$(call word-colon,2,$(v)))))
+$(foreach v,$(1),$(2)$(call word-colon,2,$(v)))
+endef
+
+# Install the boot images compiled by Soong.
+# The first file is saved in $(my_boot_image_root) and the rest are added as it's dependencies.
+my_suffix := BUILT_INSTALLED_$(my_boot_image_name)_$($(my_boot_image_arch))
+my_installed := $(call copy-many-files,$(DEXPREOPT_IMAGE_$(my_suffix)),$(my_boot_image_out))
+my_installed += $(call copy-many-files,$(DEXPREOPT_IMAGE_UNSTRIPPED_$(my_suffix)),$(my_boot_image_syms))
+my_installed += $(call copy-vdex-files,$(DEXPREOPT_IMAGE_VDEX_$(my_suffix)),$(my_boot_image_out))
+$(my_boot_image_root) += $(firstword $(my_installed))
 $(firstword $(my_installed)): $(wordlist 2,9999,$(my_installed))
-
-my_built_vdex_dir := $(dir $(call word-colon,1,$(firstword $(my_vdex_copy_pairs))))
-my_installed_vdex_dir := $(PRODUCT_OUT)$(dir $(call word-colon,2,$(firstword $(my_vdex_copy_pairs))))
-
-$(my_installed): $(my_installed_vdex_dir)% : $(my_built_vdex_dir)%
-	@echo "Install: $@"
-	@rm -f $@
-	$(copy-file-to-target)
-	mkdir -p $(dir $@)/$(TARGET_ARCH)
-	ln -sfn ../$(notdir $@) $(dir $@)/$(TARGET_ARCH)
-ifdef TARGET_2ND_ARCH
-	mkdir -p $(dir $@)/$(TARGET_2ND_ARCH)
-	ln -sfn ../$(notdir $@) $(dir $@)/$(TARGET_2ND_ARCH)
-endif
-
-my_dexpreopt_image_extra_deps := $(firstword $(my_installed))
-
-my_2nd_arch_prefix :=
-include $(BUILD_SYSTEM)/dex_preopt_libart_boot.mk
-
-ifdef TARGET_2ND_ARCH
-  my_2nd_arch_prefix := $(TARGET_2ND_ARCH_VAR_PREFIX)
-  include $(BUILD_SYSTEM)/dex_preopt_libart_boot.mk
-endif
-
-my_2nd_arch_prefix :=
-
-
-my_vdex_copy_pairs :=
 my_installed :=
-my_built_vdex_dir :=
-my_installed_vdex_dir :=
-my_dexpreopt_image_extra_deps :=
+my_suffix :=
diff --git a/core/dex_preopt_libart_boot.mk b/core/dex_preopt_libart_boot.mk
deleted file mode 100644
index 34b8526..0000000
--- a/core/dex_preopt_libart_boot.mk
+++ /dev/null
@@ -1,25 +0,0 @@
-# Rules to install a boot image built by dexpreopt_bootjars.go
-# Input variables:
-#   my_boot_image_name: the boot image to install
-#   my_2nd_arch_prefix: indicates if this is to build for the 2nd arch.
-#   my_dexpreopt_image_extra_deps: extra dependencies to add on the installed boot.art
-
-# Install the boot images compiled by Soong
-# The first file (generally boot.art) is saved as DEFAULT_DEX_PREOPT_INSTALLED_IMAGE,
-# and the rest are added as dependencies of the first.
-
-my_installed := $(call copy-many-files,$(DEXPREOPT_IMAGE_BUILT_INSTALLED_$(my_boot_image_name)_$(TARGET_$(my_2nd_arch_prefix)ARCH)),$(PRODUCT_OUT))
-$(firstword $(my_installed)): $(wordlist 2,9999,$(my_installed))
-$(my_2nd_arch_prefix)DEFAULT_DEX_PREOPT_INSTALLED_IMAGE += $(firstword $(my_installed))
-
-# Install the unstripped boot images compiled by Soong into the symbols directory
-# The first file (generally boot.art) made a dependency of DEFAULT_DEX_PREOPT_INSTALLED_IMAGE,
-# and the rest are added as dependencies of the first.
-my_installed := $(call copy-many-files,$(DEXPREOPT_IMAGE_UNSTRIPPED_BUILT_INSTALLED_$(my_boot_image_name)_$(TARGET_$(my_2nd_arch_prefix)ARCH)),$(TARGET_OUT_UNSTRIPPED))
-$(firstword $(my_installed)): $(wordlist 2,9999,$(my_installed))
-$($(my_2nd_arch_prefix)DEFAULT_DEX_PREOPT_INSTALLED_IMAGE): $(firstword $(my_installed))
-
-$($(my_2nd_arch_prefix)DEFAULT_DEX_PREOPT_INSTALLED_IMAGE): $(my_dexpreopt_image_extra_deps)
-
-my_installed :=
-my_built_installed :=
diff --git a/core/envsetup.mk b/core/envsetup.mk
index e38329d..ac3d5cf 100644
--- a/core/envsetup.mk
+++ b/core/envsetup.mk
@@ -259,8 +259,6 @@
 # Jars present in the ART apex. These should match exactly the list of
 # Java libraries in the ART apex build rule.
 ART_APEX_JARS := core-oj core-libart core-icu4j okhttp bouncycastle apache-xml
-TARGET_CORE_JARS := $(ART_APEX_JARS) conscrypt
-HOST_CORE_JARS := $(addsuffix -hostdex,$(TARGET_CORE_JARS))
 #################################################################
 
 # Read the product specs so we can get TARGET_DEVICE and other
diff --git a/core/package_internal.mk b/core/package_internal.mk
index 7bbaeb6..e680df7 100644
--- a/core/package_internal.mk
+++ b/core/package_internal.mk
@@ -100,19 +100,19 @@
 # Determine whether auto-RRO is enabled for this package.
 enforce_rro_enabled :=
 ifneq (,$(filter *, $(PRODUCT_ENFORCE_RRO_TARGETS)))
-  # * means all system APKs, so enable conditionally based on module path.
+  # * means all system and system_ext APKs, so enable conditionally based on module path.
+  # Note that modules in PRODUCT_ENFORCE_RRO_EXEMPTED_TARGETS are excluded even if it is '*'
 
   # Note that base_rules.mk has not yet been included, so it's likely that only
   # one of LOCAL_MODULE_PATH and the LOCAL_X_MODULE flags has been set.
   ifeq (,$(LOCAL_MODULE_PATH))
-    non_system_module := $(filter true,\
+    non_rro_target_module := $(filter true,\
         $(LOCAL_ODM_MODULE) \
         $(LOCAL_OEM_MODULE) \
         $(LOCAL_PRODUCT_MODULE) \
-        $(LOCAL_SYSTEM_EXT_MODULE) \
         $(LOCAL_PROPRIETARY_MODULE) \
         $(LOCAL_VENDOR_MODULE))
-    enforce_rro_enabled := $(if $(non_system_module),,true)
+    enforce_rro_enabled := $(if $(non_rro_target_module),,true)
   else ifneq ($(filter $(TARGET_OUT)/%,$(LOCAL_MODULE_PATH)),)
     enforce_rro_enabled := true
   endif
@@ -120,6 +120,12 @@
   enforce_rro_enabled := true
 endif
 
+# TODO(b/150820813) Some modules depend on static overlay, remove this after eliminating the dependency.
+ifneq (,$(filter $(LOCAL_PACKAGE_NAME), $(PRODUCT_ENFORCE_RRO_EXEMPTED_TARGETS)))
+  enforce_rro_enabled :=
+endif
+
+
 product_package_overlays := $(strip \
     $(wildcard $(foreach dir, $(PRODUCT_PACKAGE_OVERLAYS), \
       $(addprefix $(dir)/, $(LOCAL_RESOURCE_DIR)))))
diff --git a/core/product.mk b/core/product.mk
index 25a9c44..b497abb 100644
--- a/core/product.mk
+++ b/core/product.mk
@@ -193,6 +193,9 @@
 # Package list to apply enforcing RRO.
 _product_list_vars += PRODUCT_ENFORCE_RRO_TARGETS
 
+# Packages to skip auto-generating RROs for when PRODUCT_ENFORCE_RRO_TARGETS is set to *.
+_product_list_vars += PRODUCT_ENFORCE_RRO_EXEMPTED_TARGETS
+
 _product_list_vars += PRODUCT_SDK_ATREE_FILES
 _product_list_vars += PRODUCT_SDK_ADDON_NAME
 _product_list_vars += PRODUCT_SDK_ADDON_COPY_FILES
@@ -213,6 +216,12 @@
 
 # A list of module names of BOOTCLASSPATH (jar files)
 _product_list_vars += PRODUCT_BOOT_JARS
+
+# A list of extra BOOTCLASSPATH jars (to be appended after common jars).
+# Products that include device-specific makefiles before AOSP makefiles should use this
+# instead of PRODUCT_BOOT_JARS, so that device-specific jars go after common jars.
+_product_list_vars += PRODUCT_BOOT_JARS_EXTRA
+
 _product_list_vars += PRODUCT_SUPPORTS_BOOT_SIGNER
 _product_list_vars += PRODUCT_SUPPORTS_VBOOT
 _product_list_vars += PRODUCT_SUPPORTS_VERITY
diff --git a/core/product_config.mk b/core/product_config.mk
index c4361d0..aabd472 100644
--- a/core/product_config.mk
+++ b/core/product_config.mk
@@ -228,6 +228,9 @@
 PRODUCT_AAPT_CONFIG_SP := $(PRODUCT_AAPT_CONFIG)
 PRODUCT_AAPT_CONFIG := $(subst $(space),$(comma),$(PRODUCT_AAPT_CONFIG))
 
+# Extra boot jars must be appended at the end after common boot jars.
+PRODUCT_BOOT_JARS += $(PRODUCT_BOOT_JARS_EXTRA)
+
 ifndef PRODUCT_SYSTEM_NAME
   PRODUCT_SYSTEM_NAME := $(PRODUCT_NAME)
 endif
diff --git a/core/soong_app_prebuilt.mk b/core/soong_app_prebuilt.mk
index 0a5ba9d..a001e3a 100644
--- a/core/soong_app_prebuilt.mk
+++ b/core/soong_app_prebuilt.mk
@@ -202,4 +202,11 @@
   )
 endif
 
+ifdef LOCAL_PREBUILT_COVERAGE_ARCHIVE
+  my_coverage_dir := $(TARGET_OUT_COVERAGE)/$(patsubst $(PRODUCT_OUT)/%,%,$(my_module_path))
+  my_coverage_copy_pairs := $(foreach f,$(LOCAL_PREBUILT_COVERAGE_ARCHIVE),$(f):$(my_coverage_dir)/$(notdir  $(f)))
+  my_coverage_files := $(call copy-many-files,$(my_coverage_copy_pairs))
+  $(LOCAL_INSTALLED_MODULE): $(my_coverage_files)
+endif
+
 SOONG_ALREADY_CONV := $(SOONG_ALREADY_CONV) $(LOCAL_MODULE)
diff --git a/core/soong_config.mk b/core/soong_config.mk
index abe1923..c91639c 100644
--- a/core/soong_config.mk
+++ b/core/soong_config.mk
@@ -81,6 +81,7 @@
 $(call add_json_list, DeviceResourceOverlays,            $(DEVICE_PACKAGE_OVERLAYS))
 $(call add_json_list, ProductResourceOverlays,           $(PRODUCT_PACKAGE_OVERLAYS))
 $(call add_json_list, EnforceRROTargets,                 $(PRODUCT_ENFORCE_RRO_TARGETS))
+$(call add_json_list, EnforceRROExemptedTargets,         $(PRODUCT_ENFORCE_RRO_EXEMPTED_TARGETS))
 $(call add_json_list, EnforceRROExcludedOverlays,        $(PRODUCT_ENFORCE_RRO_EXCLUDED_OVERLAYS))
 
 $(call add_json_str,  AAPTCharacteristics,               $(TARGET_AAPT_CHARACTERISTICS))
@@ -116,6 +117,8 @@
 $(call add_json_list, CoveragePaths,                     $(COVERAGE_PATHS))
 $(call add_json_list, CoverageExcludePaths,              $(COVERAGE_EXCLUDE_PATHS))
 
+$(call add_json_bool, SamplingPGO,                       $(filter true,$(SAMPLING_PGO)))
+
 $(call add_json_bool, ArtUseReadBarrier,                 $(call invert_bool,$(filter false,$(PRODUCT_ART_USE_READ_BARRIER))))
 $(call add_json_bool, Binder32bit,                       $(BINDER32BIT))
 $(call add_json_str,  BtConfigIncludeDir,                $(BOARD_BLUETOOTH_BDROID_BUILDCFG_INCLUDE_DIR))
diff --git a/target/board/Android.mk b/target/board/Android.mk
index 0c326b9..9edc85c 100644
--- a/target/board/Android.mk
+++ b/target/board/Android.mk
@@ -52,13 +52,13 @@
 include $(BUILD_PREBUILT)
 endif
 
-# DEVICE_MANIFEST_SKUS: a list of SKUS where DEVICE_MANIFEST_<sku>_FILE is defined.
+# DEVICE_MANIFEST_SKUS: a list of SKUS where DEVICE_MANIFEST_<sku>_FILES is defined.
 ifdef DEVICE_MANIFEST_SKUS
 
 # Install /vendor/etc/vintf/manifest_$(sku).xml
 # $(1): sku
 define _add_device_sku_manifest
-my_fragment_files_var := DEVICE_MANIFEST_$$(call to-upper,$(1))_FILE
+my_fragment_files_var := DEVICE_MANIFEST_$$(call to-upper,$(1))_FILES
 ifndef $$(my_fragment_files_var)
 $$(error $(1) is in DEVICE_MANIFEST_SKUS but $$(my_fragment_files_var) is not defined)
 endif
@@ -72,9 +72,9 @@
 GEN := $$(local-generated-sources-dir)/manifest_$(1).xml
 $$(GEN): PRIVATE_SRC_FILES := $$(my_fragment_files)
 $$(GEN): $$(my_fragment_files) $$(HOST_OUT_EXECUTABLES)/assemble_vintf
-	BOARD_SEPOLICY_VERS=$(BOARD_SEPOLICY_VERS) \
-	PRODUCT_ENFORCE_VINTF_MANIFEST=$(PRODUCT_ENFORCE_VINTF_MANIFEST) \
-	PRODUCT_SHIPPING_API_LEVEL=$(PRODUCT_SHIPPING_API_LEVEL) \
+	BOARD_SEPOLICY_VERS=$$(BOARD_SEPOLICY_VERS) \
+	PRODUCT_ENFORCE_VINTF_MANIFEST=$$(PRODUCT_ENFORCE_VINTF_MANIFEST) \
+	PRODUCT_SHIPPING_API_LEVEL=$$(PRODUCT_SHIPPING_API_LEVEL) \
 	$$(HOST_OUT_EXECUTABLES)/assemble_vintf -o $$@ \
 		-i $$(call normalize-path-list,$$(PRIVATE_SRC_FILES))
 
diff --git a/target/product/base_system.mk b/target/product/base_system.mk
index b795dbb..d9eb7c3 100644
--- a/target/product/base_system.mk
+++ b/target/product/base_system.mk
@@ -27,6 +27,7 @@
     android.test.base \
     android.test.mock \
     android.test.runner \
+    ANGLE \
     apexd \
     appops \
     app_process \
@@ -311,8 +312,8 @@
     tz_version_host \
     tz_version_host_tzdata_apex \
 
-ifeq ($(TARGET_CORE_JARS),)
-$(error TARGET_CORE_JARS is empty; cannot initialize PRODUCT_BOOT_JARS variable)
+ifeq ($(ART_APEX_JARS),)
+$(error ART_APEX_JARS is empty; cannot initialize PRODUCT_BOOT_JARS variable)
 endif
 
 # The order matters for runtime class lookup performance.
diff --git a/target/product/base_system_ext.mk b/target/product/base_system_ext.mk
index 6847bfa..b67549a 100644
--- a/target/product/base_system_ext.mk
+++ b/target/product/base_system_ext.mk
@@ -17,4 +17,5 @@
 # Base modules and settings for the system_ext partition.
 PRODUCT_PACKAGES += \
     group_system_ext \
+    system_ext_manifest.xml \
     passwd_system_ext \
diff --git a/target/product/mainline_system.mk b/target/product/mainline_system.mk
index ccbc907..a8b75e0 100644
--- a/target/product/mainline_system.mk
+++ b/target/product/mainline_system.mk
@@ -125,6 +125,9 @@
 
 PRODUCT_ENFORCE_RRO_TARGETS := *
 
+# TODO(b/150820813) Settings depends on static overlay, remove this after eliminating the dependency.
+PRODUCT_ENFORCE_RRO_EXEMPTED_TARGETS := Settings
+
 PRODUCT_NAME := mainline_system
 PRODUCT_BRAND := generic
 
diff --git a/target/product/media_system.mk b/target/product/media_system.mk
index 5749ed5..a83e609 100644
--- a/target/product/media_system.mk
+++ b/target/product/media_system.mk
@@ -50,10 +50,10 @@
 
 # The order here is the same order they end up on the classpath, so it matters.
 PRODUCT_SYSTEM_SERVER_JARS := \
+    com.android.location.provider \
     services \
     ethernet-service \
     wifi-service \
-    com.android.location.provider \
 
 # system server jars which are updated via apex modules.
 # The values should be of the format <apex name>:<jar name>
diff --git a/target/product/runtime_libart.mk b/target/product/runtime_libart.mk
index b8cb2ff..5184016 100644
--- a/target/product/runtime_libart.mk
+++ b/target/product/runtime_libart.mk
@@ -16,10 +16,6 @@
 
 # Provides a functioning ART environment without Android frameworks
 
-ifeq ($(TARGET_CORE_JARS),)
-$(error TARGET_CORE_JARS is empty; cannot update PRODUCT_PACKAGES variable)
-endif
-
 # Additional mixins to the boot classpath.
 PRODUCT_PACKAGES += \
     android.test.base \
@@ -33,8 +29,7 @@
 
 # ART APEX module.
 # Note that this package includes the minimal boot classpath JARs (listed in
-# TARGET_CORE_JARS), which should no longer be added directly to
-# PRODUCT_PACKAGES.
+# ART_APEX_JARS), which should no longer be added directly to PRODUCT_PACKAGES.
 PRODUCT_PACKAGES += com.android.art
 PRODUCT_HOST_PACKAGES += com.android.art
 
diff --git a/tools/releasetools/Android.bp b/tools/releasetools/Android.bp
index 90a6485..f29ec90 100644
--- a/tools/releasetools/Android.bp
+++ b/tools/releasetools/Android.bp
@@ -188,6 +188,7 @@
         "imgdiff",
         "minigzip",
         "mkbootfs",
+        "signapk",
     ],
 }
 
diff --git a/tools/releasetools/apex_utils.py b/tools/releasetools/apex_utils.py
index 4fac6f3..9e27d29 100644
--- a/tools/releasetools/apex_utils.py
+++ b/tools/releasetools/apex_utils.py
@@ -27,6 +27,8 @@
 
 OPTIONS = common.OPTIONS
 
+APEX_PAYLOAD_IMAGE = 'apex_payload.img'
+
 
 class ApexInfoError(Exception):
   """An Exception raised during Apex Information command."""
@@ -50,15 +52,11 @@
     self.key_passwords = key_passwords
     self.codename_to_api_level_map = codename_to_api_level_map
 
-  def ProcessApexFile(self, apk_keys, payload_key, payload_public_key,
-                      signing_args=None):
+  def ProcessApexFile(self, apk_keys, payload_key):
     """Scans and signs the apk files and repack the apex
 
     Args:
       apk_keys: A dict that holds the signing keys for apk files.
-      payload_key: The path to the apex payload signing key.
-      payload_public_key: The path to the public key corresponding to the
-       payload signing key.
 
     Returns:
       The repacked apex file containing the signed apk files.
@@ -89,8 +87,7 @@
       logger.info('No apk file has been signed in %s', self.apex_path)
       return self.apex_path
 
-    return self.RepackApexPayload(payload_dir, payload_key, payload_public_key,
-                                  signing_args)
+    return self.RepackApexPayload(payload_dir, payload_key)
 
   def ExtractApexPayloadAndSignApks(self, apk_entries, apk_keys):
     """Extracts the payload image and signs the containing apk files."""
@@ -118,27 +115,15 @@
       has_signed_apk = True
     return payload_dir, has_signed_apk
 
-  def RepackApexPayload(self, payload_dir, payload_key, payload_public_key,
-                        signing_args=None):
+  def RepackApexPayload(self, payload_dir, payload_key):
     """Rebuilds the apex file with the updated payload directory."""
     apex_dir = common.MakeTempDir()
     # Extract the apex file and reuse its meta files as repack parameters.
     common.UnzipToDir(self.apex_path, apex_dir)
-
-    android_jar_path = common.OPTIONS.android_jar_path
-    if not android_jar_path:
-      android_jar_path = os.path.join(os.environ.get('ANDROID_BUILD_TOP', ''),
-                                      'prebuilts', 'sdk', 'current', 'public',
-                                      'android.jar')
-      logger.warning('android_jar_path not found in options, falling back to'
-                     ' use %s', android_jar_path)
-
     arguments_dict = {
         'manifest': os.path.join(apex_dir, 'apex_manifest.pb'),
         'build_info': os.path.join(apex_dir, 'apex_build_info.pb'),
-        'android_jar_path': android_jar_path,
         'key': payload_key,
-        'pubkey': payload_public_key,
     }
     for filename in arguments_dict.values():
       assert os.path.exists(filename), 'file {} not found'.format(filename)
@@ -151,29 +136,30 @@
       elif os.path.isdir(path):
         shutil.rmtree(path)
 
-    repacked_apex = common.MakeTempFile(suffix='.apex')
-    repack_cmd = ['apexer', '--force', '--include_build_info',
-                  '--do_not_check_keyname', '--apexer_tool_path',
-                  os.getenv('PATH')]
+    # TODO(xunchang) the signing process can be improved by using
+    # '--unsigned_payload_only'. But we need to parse the vbmeta earlier for
+    # the signing arguments, e.g. algorithm, salt, etc.
+    payload_img = os.path.join(apex_dir, APEX_PAYLOAD_IMAGE)
+    generate_image_cmd = ['apexer', '--force', '--payload_only',
+                          '--do_not_check_keyname', '--apexer_tool_path',
+                          os.getenv('PATH')]
     for key, val in arguments_dict.items():
-      repack_cmd.extend(['--' + key, val])
-    # Add quote to the signing_args as we will pass
-    # --signing_args "--signing_helper_with_files=%path" to apexer
-    if signing_args:
-      repack_cmd.extend(['--signing_args', '"{}"'.format(signing_args)])
+      generate_image_cmd.extend(['--' + key, val])
     # optional arguments for apex repacking
     manifest_json = os.path.join(apex_dir, 'apex_manifest.json')
     if os.path.exists(manifest_json):
-      repack_cmd.extend(['--manifest_json', manifest_json])
-    assets_dir = os.path.join(apex_dir, 'assets')
-    if os.path.isdir(assets_dir):
-      repack_cmd.extend(['--assets_dir', assets_dir])
-    repack_cmd.extend([payload_dir, repacked_apex])
+      generate_image_cmd.extend(['--manifest_json', manifest_json])
+    generate_image_cmd.extend([payload_dir, payload_img])
     if OPTIONS.verbose:
-      repack_cmd.append('-v')
-    common.RunAndCheckOutput(repack_cmd)
+      generate_image_cmd.append('-v')
+    common.RunAndCheckOutput(generate_image_cmd)
 
-    return repacked_apex
+    # Add the payload image back to the apex file.
+    common.ZipDelete(self.apex_path, APEX_PAYLOAD_IMAGE)
+    with zipfile.ZipFile(self.apex_path, 'a') as output_apex:
+      common.ZipWrite(output_apex, payload_img, APEX_PAYLOAD_IMAGE,
+                      compress_type=zipfile.ZIP_STORED)
+    return self.apex_path
 
 
 def SignApexPayload(avbtool, payload_file, payload_key_path, payload_key_name,
@@ -311,16 +297,13 @@
   with open(apex_file, 'wb') as apex_fp:
     apex_fp.write(apex_data)
 
-  APEX_PAYLOAD_IMAGE = 'apex_payload.img'
   APEX_PUBKEY = 'apex_pubkey'
 
   # 1. Extract the apex payload image and sign the containing apk files. Repack
   # the apex file after signing.
-  payload_public_key = common.ExtractAvbPublicKey(avbtool, payload_key)
   apk_signer = ApexApkSigner(apex_file, container_pw,
                              codename_to_api_level_map)
-  apex_file = apk_signer.ProcessApexFile(apk_keys, payload_key,
-                                         payload_public_key, signing_args)
+  apex_file = apk_signer.ProcessApexFile(apk_keys, payload_key)
 
   # 2a. Extract and sign the APEX_PAYLOAD_IMAGE entry with the given
   # payload_key.
@@ -341,7 +324,7 @@
       signing_args)
 
   # 2b. Update the embedded payload public key.
-
+  payload_public_key = common.ExtractAvbPublicKey(avbtool, payload_key)
   common.ZipDelete(apex_file, APEX_PAYLOAD_IMAGE)
   if APEX_PUBKEY in zip_items:
     common.ZipDelete(apex_file, APEX_PUBKEY)
diff --git a/tools/releasetools/check_target_files_vintf.py b/tools/releasetools/check_target_files_vintf.py
index f41df37..b3d491f 100755
--- a/tools/releasetools/check_target_files_vintf.py
+++ b/tools/releasetools/check_target_files_vintf.py
@@ -67,13 +67,18 @@
 
 
 def GetArgsForSkus(info_dict):
-  skus = info_dict.get('vintf_odm_manifest_skus', '').strip().split()
-  if not skus:
-    logger.info("ODM_MANIFEST_SKUS is not defined. Check once without SKUs.")
-    skus = ['']
-  return [['--property', 'ro.boot.product.hardware.sku=' + sku]
-          for sku in skus]
+  odm_skus = info_dict.get('vintf_odm_manifest_skus', '').strip().split()
+  if info_dict.get('vintf_include_empty_odm_sku', '') == "true" or not odm_skus:
+    odm_skus += ['']
 
+  vendor_skus = info_dict.get('vintf_vendor_manifest_skus', '').strip().split()
+  if info_dict.get('vintf_include_empty_vendor_sku', '') == "true" or \
+      not vendor_skus:
+    vendor_skus += ['']
+
+  return [['--property', 'ro.boot.product.hardware.sku=' + odm_sku,
+           '--property', 'ro.boot.product.vendor.sku=' + vendor_sku]
+          for odm_sku in odm_skus for vendor_sku in vendor_skus]
 
 def GetArgsForShippingApiLevel(info_dict):
   shipping_api_level = info_dict['vendor.build.prop'].get(
@@ -89,7 +94,7 @@
   config_path = os.path.join(input_tmp, 'META/kernel_configs.txt')
 
   if not os.path.isfile(version_path) or not os.path.isfile(config_path):
-    logger.info('Skipping kernel config checks because ' +
+    logger.info('Skipping kernel config checks because '
                 'PRODUCT_OTA_ENFORCE_VINTF_KERNEL_REQUIREMENTS is not set')
     return []
 
diff --git a/tools/releasetools/ota_from_target_files.py b/tools/releasetools/ota_from_target_files.py
index 7a0d994..92a46a2 100755
--- a/tools/releasetools/ota_from_target_files.py
+++ b/tools/releasetools/ota_from_target_files.py
@@ -318,7 +318,7 @@
     common.RunAndCheckOutput(cmd)
     with open(out_signature_size_file) as f:
       signature_size = f.read().rstrip()
-    logger.info("% outputs the maximum signature size: %", cmd[0],
+    logger.info("%s outputs the maximum signature size: %s", cmd[0],
                 signature_size)
     return int(signature_size)
 
@@ -631,7 +631,7 @@
     partition_target_info = target_info["fstab"]["/" + name]
     disable_imgdiff = (partition_source_info.fs_type == "squashfs" or
                        partition_target_info.fs_type == "squashfs")
-    return common.BlockDifference(name, partition_src, partition_tgt,
+    return common.BlockDifference(name, partition_tgt, partition_src,
                                   check_first_block,
                                   version=blockimgdiff_version,
                                   disable_imgdiff=disable_imgdiff)
diff --git a/tools/releasetools/test_apex_utils.py b/tools/releasetools/test_apex_utils.py
index 07284ad..e19bc90 100644
--- a/tools/releasetools/test_apex_utils.py
+++ b/tools/releasetools/test_apex_utils.py
@@ -14,8 +14,10 @@
 # limitations under the License.
 #
 
+import re
 import os
 import os.path
+import shutil
 import zipfile
 
 import apex_utils
@@ -32,6 +34,7 @@
     self.testdata_dir = test_utils.get_testdata_dir()
     # The default payload signing key.
     self.payload_key = os.path.join(self.testdata_dir, 'testkey.key')
+    self.apex_with_apk = os.path.join(self.testdata_dir, 'has_apk.apex')
 
     common.OPTIONS.search_path = test_utils.get_search_path()
 
@@ -134,35 +137,43 @@
   def test_ApexApkSigner_noApkPresent(self):
     apex_path = os.path.join(self.testdata_dir, 'foo.apex')
     signer = apex_utils.ApexApkSigner(apex_path, None, None)
-    processed_apex = signer.ProcessApexFile({}, self.payload_key,
-                                            None)
+    processed_apex = signer.ProcessApexFile({}, self.payload_key)
     self.assertEqual(apex_path, processed_apex)
 
   @test_utils.SkipIfExternalToolsUnavailable()
   def test_ApexApkSigner_apkKeyNotPresent(self):
-    apex_path = os.path.join(self.testdata_dir, 'has_apk.apex')
+    apex_path = common.MakeTempFile(suffix='.apex')
+    shutil.copy(self.apex_with_apk, apex_path)
     signer = apex_utils.ApexApkSigner(apex_path, None, None)
-    self.assertRaises(apex_utils.ApexSigningError, signer.ProcessApexFile, {},
-                      self.payload_key, None)
+    self.assertRaises(apex_utils.ApexSigningError, signer.ProcessApexFile,
+                      {}, self.payload_key)
 
   @test_utils.SkipIfExternalToolsUnavailable()
   def test_ApexApkSigner_signApk(self):
-    apex_path = os.path.join(self.testdata_dir, 'has_apk.apex')
+    apex_path = common.MakeTempFile(suffix='.apex')
+    shutil.copy(self.apex_with_apk, apex_path)
     signer = apex_utils.ApexApkSigner(apex_path, None, None)
     apk_keys = {'wifi-service-resources.apk': os.path.join(
         self.testdata_dir, 'testkey')}
 
     self.payload_key = os.path.join(self.testdata_dir, 'testkey_RSA4096.key')
-    payload_pubkey = common.ExtractAvbPublicKey('avbtool',
-                                                self.payload_key)
-    signer.ProcessApexFile(apk_keys, self.payload_key, payload_pubkey)
+    apex_file = signer.ProcessApexFile(apk_keys, self.payload_key)
+    package_name_extract_cmd = ['aapt', 'dump', 'badging', apex_file]
+    output = common.RunAndCheckOutput(package_name_extract_cmd)
+    for line in output.splitlines():
+      # Sample output from aapt: "package: name='com.google.android.wifi'
+      # versionCode='1' versionName='' platformBuildVersionName='R'
+      # compileSdkVersion='29' compileSdkVersionCodename='R'"
+      match = re.search(r"^package:.* name='([\w|\.]+)'", line, re.IGNORECASE)
+      if match:
+        package_name = match.group(1)
+    self.assertEquals('com.google.android.wifi', package_name)
 
   @test_utils.SkipIfExternalToolsUnavailable()
   def test_ApexApkSigner_noAssetDir(self):
-    apex_path = os.path.join(self.testdata_dir, 'has_apk.apex')
     no_asset = common.MakeTempFile(suffix='.apex')
     with zipfile.ZipFile(no_asset, 'w') as output_zip:
-      with zipfile.ZipFile(apex_path, 'r') as input_zip:
+      with zipfile.ZipFile(self.apex_with_apk, 'r') as input_zip:
         name_list = input_zip.namelist()
         for name in name_list:
           if not name.startswith('assets'):
@@ -173,23 +184,4 @@
         self.testdata_dir, 'testkey')}
 
     self.payload_key = os.path.join(self.testdata_dir, 'testkey_RSA4096.key')
-    payload_pubkey = common.ExtractAvbPublicKey('avbtool',
-                                                self.payload_key)
-    signer.ProcessApexFile(apk_keys, self.payload_key, payload_pubkey)
-
-  @test_utils.SkipIfExternalToolsUnavailable()
-  def test_ApexApkSigner_withSignerHelper(self):
-    apex_path = os.path.join(self.testdata_dir, 'has_apk.apex')
-    signer = apex_utils.ApexApkSigner(apex_path, None, None)
-    apk_keys = {'wifi-service-resources.apk': os.path.join(
-        self.testdata_dir, 'testkey')}
-
-    self.payload_key = os.path.join(self.testdata_dir, 'testkey_RSA4096.key')
-    payload_pubkey = common.ExtractAvbPublicKey('avbtool', self.payload_key)
-
-    signing_helper = os.path.join(self.testdata_dir, 'signing_helper.sh')
-    os.chmod(signing_helper, 0o700)
-    payload_signer_args = '--signing_helper_with_files={}'.format(
-        signing_helper)
-    signer.ProcessApexFile(apk_keys, self.payload_key, payload_pubkey,
-                           payload_signer_args)
+    signer.ProcessApexFile(apk_keys, self.payload_key)