diff --git a/Changes.md b/Changes.md
index 7440220..baa5e6e 100644
--- a/Changes.md
+++ b/Changes.md
@@ -1,6 +1,81 @@
 # Build System Changes for Android.mk Writers
 
-### `export` and `unexport` deprecation  {#export_keyword}
+## `.PHONY` rule enforcement  {#phony_targets}
+
+There are several new warnings/errors meant to ensure the proper use of
+`.PHONY` targets in order to improve the speed and reliability of incremental
+builds.
+
+`.PHONY`-marked targets are often used as shortcuts to provide "friendly" names
+for real files to be built, but any target marked with `.PHONY` is also always
+considered dirty, needing to be rebuilt every build. This isn't a problem for
+aliases or one-off user-requested operations, but if real builds steps depend
+on a `.PHONY` target, it can get quite expensive for what should be a tiny
+build.
+
+``` make
+...mk:42: warning: PHONY target "out/.../foo" looks like a real file (contains a "/")
+```
+
+Between this warning and the next, we're requiring that `.PHONY` targets do not
+have "/" in them, and real file targets do have a "/". This makes it more
+obvious when reading makefiles what is happening, and will help the build
+system differentiate these in the future too.
+
+``` make
+...mk:42: warning: writing to readonly directory: "kernel-modules"
+```
+
+This warning will show up for one of two reasons:
+
+1. The target isn't intended to be a real file, and should be marked with
+   `.PHONY`. This would be the case for this example.
+2. The target is a real file, but it's outside the output directories. All
+   outputs from the build system should be within the output directory,
+   otherwise `m clean` is unable to clean the build, and future builds may not
+   work properly.
+
+``` make
+...mk:42: warning: real file "out/.../foo" depends on PHONY target "buildbins"
+```
+
+If the first target isn't intended to be a real file, then it should be marked
+with `.PHONY`, which will satisfy this warning. This isn't the case for this
+example, as we require `.PHONY` targets not to have '/' in them.
+
+If the second (PHONY) target is a real file, it may unnecessarily be marked
+with `.PHONY`.
+
+### `.PHONY` and calling other build systems
+
+One common pattern (mostly outside AOSP) that we've seen hit these warning is
+when building with external build systems (firmware, bootloader, kernel, etc).
+Those are often marked as `.PHONY` because the Android build system doesn't
+have enough dependencies to know when to run the other build system again
+during an incremental build.
+
+We recommend to build these outside of Android, and deliver prebuilts into the
+Android tree instead of decreasing the speed and reliability of the incremental
+Android build.
+
+In cases where that's not desired, to preserve the speed of Android
+incrementals, over-specifying dependencies is likely a better option than
+marking it with `.PHONY`:
+
+``` make
+out/target/.../zImage: $(sort $(shell find -L $(KERNEL_SRCDIR)))
+	...
+```
+
+For reliability, many of these other build systems do not guarantee the same
+level of incremental build assurances as the Android Build is attempting to do
+-- without custom checks, Make doesn't rebuild objects when CFLAGS change, etc.
+In order to fix this, our recommendation is to do clean builds for each of
+these external build systems every time anything they rely on changes. For
+relatively smaller builds (like the kernel), this may be reasonable as long as
+you're not trying to actively debug the kernel.
+
+## `export` and `unexport` deprecation  {#export_keyword}
 
 The `export` and `unexport` keywords have been deprecated, and will throw
 warnings or errors depending on where they are used.
diff --git a/core/Makefile b/core/Makefile
index 0a112f8..a9c7abe 100644
--- a/core/Makefile
+++ b/core/Makefile
@@ -1475,15 +1475,26 @@
 recovery_ramdisk := $(PRODUCT_OUT)/ramdisk-recovery.img
 recovery_resources_common := $(call include-path-for, recovery)/res
 
-# Set recovery_density to the density bucket of the device.
-recovery_density := unknown
+# Set recovery_density to a density bucket based on PRODUCT_AAPT_PREF_CONFIG if set. Otherwise use
+# the default medium density.
 ifneq (,$(PRODUCT_AAPT_PREF_CONFIG))
-# If PRODUCT_AAPT_PREF_CONFIG includes a dpi bucket, then use that value.
+# If PRODUCT_AAPT_PREF_CONFIG includes a non-numeric dpi bucket, always perfer that value.
 recovery_density := $(filter %dpi,$(PRODUCT_AAPT_PREF_CONFIG))
-else
-# Otherwise, use the default medium density.
-recovery_densities := mdpi
+ifeq (,$(filter xxxhdpi xxhdpi xhdpi hdpi mdpi,$(recovery_density)))
+recovery_density_value := $(patsubst %dpi,%,$(recovery_density))
+# Map the numeric dpi value to a bucket. We roughly use the medium point between the primary
+# densities to split buckets.
+# ------160------240------320----------480------------640------
+#       mdpi     hdpi    xhdpi        xxhdpi        xxxhdpi
+recovery_density := $(strip \
+  $(or $(if $(filter $(shell echo $$(($(recovery_density_value) >= 560))),1),xxxhdpi),\
+       $(if $(filter $(shell echo $$(($(recovery_density_value) >= 400))),1),xxhdpi),\
+       $(if $(filter $(shell echo $$(($(recovery_density_value) >= 280))),1),xhdpi),\
+       $(if $(filter $(shell echo $$(($(recovery_density_value) >= 200))),1),hdpi,mdpi)))
 endif
+else # PRODUCT_AAPT_PREF_CONFIG is empty
+recovery_density := mdpi
+endif # PRODUCT_AAPT_PREF_CONFIG
 
 ifneq (,$(wildcard $(recovery_resources_common)-$(recovery_density)))
 recovery_resources_common := $(recovery_resources_common)-$(recovery_density)
@@ -1491,12 +1502,10 @@
 recovery_resources_common := $(recovery_resources_common)-xhdpi
 endif
 
-# Select the 18x32 font on high-density devices (xhdpi and up); and
-# the 12x22 font on other devices.  Note that the font selected here
-# can be overridden for a particular device by putting a font.png in
-# its private recovery resources.
-
-ifneq (,$(filter xxxhdpi 560dpi xxhdpi 400dpi xhdpi,$(recovery_density)))
+# Select the 18x32 font on high-density devices (xhdpi and up); and the 12x22 font on other devices.
+# Note that the font selected here can be overridden for a particular device by putting a font.png
+# in its private recovery resources.
+ifneq (,$(filter xxxhdpi xxhdpi xhdpi,$(recovery_density)))
 recovery_font := $(call include-path-for, recovery)/fonts/18x32.png
 else
 recovery_font := $(call include-path-for, recovery)/fonts/12x22.png
@@ -3174,6 +3183,7 @@
 		$(HOST_OUT_EXECUTABLES)/fs_config \
 		$(HOST_OUT_EXECUTABLES)/imgdiff \
 		$(HOST_OUT_EXECUTABLES)/bsdiff \
+		$(HOST_OUT_EXECUTABLES)/care_map_generator \
 		$(BUILD_IMAGE_SRCS) \
 		$(BUILT_ASSEMBLED_SYSTEM_MANIFEST) \
 		$(BUILT_ASSEMBLED_VENDOR_MANIFEST) \
diff --git a/core/config.mk b/core/config.mk
index dd881db..5c4136a 100644
--- a/core/config.mk
+++ b/core/config.mk
@@ -84,6 +84,7 @@
   ,See $(CHANGES_URL)#other_envsetup_variables)
 $(KATI_obsolete_var PRODUCT_COMPATIBILITY_MATRIX_LEVEL_OVERRIDE,Set FCM Version in device manifest instead. See $(CHANGES_URL)#PRODUCT_COMPATIBILITY_MATRIX_LEVEL_OVERRIDE)
 $(KATI_obsolete_var USE_CLANG_PLATFORM_BUILD,Clang is the only supported Android compiler. See $(CHANGES_URL)#USE_CLANG_PLATFORM_BUILD)
+$(KATI_obsolete_var BUILD_DROIDDOC,Droiddoc is only supported in Soong. See details on build/soong/java/droiddoc.go)
 
 # This is marked as obsolete in envsetup.mk after reading the BoardConfig.mk
 $(KATI_deprecate_export It is a global setting. See $(CHANGES_URL)#export_keyword)
@@ -146,7 +147,6 @@
 BUILD_JAVA_LIBRARY:= $(BUILD_SYSTEM)/java_library.mk
 BUILD_STATIC_JAVA_LIBRARY:= $(BUILD_SYSTEM)/static_java_library.mk
 BUILD_HOST_JAVA_LIBRARY:= $(BUILD_SYSTEM)/host_java_library.mk
-BUILD_DROIDDOC:= $(BUILD_SYSTEM)/droiddoc.mk
 BUILD_APIDIFF:= $(BUILD_SYSTEM)/apidiff.mk
 BUILD_COPY_HEADERS := $(BUILD_SYSTEM)/copy_headers.mk
 BUILD_NATIVE_TEST := $(BUILD_SYSTEM)/native_test.mk
diff --git a/core/droiddoc.mk b/core/droiddoc.mk
deleted file mode 100644
index 587d284..0000000
--- a/core/droiddoc.mk
+++ /dev/null
@@ -1,294 +0,0 @@
-#
-# Copyright (C) 2008 The Android Open Source Project
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#      http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-#
-
-$(call record-module-type,DROIDDOC)
-##
-##
-## Common to both droiddoc and javadoc
-##
-##
-
-LOCAL_IS_HOST_MODULE := $(call true-or-empty,$(LOCAL_IS_HOST_MODULE))
-ifeq ($(LOCAL_IS_HOST_MODULE),true)
-my_prefix := HOST_
-LOCAL_HOST_PREFIX :=
-else
-my_prefix := TARGET_
-endif
-
-LOCAL_MODULE_CLASS := $(strip $(LOCAL_MODULE_CLASS))
-ifndef LOCAL_MODULE_CLASS
-$(error $(LOCAL_PATH): LOCAL_MODULE_CLASS not defined)
-endif
-
-full_src_files := $(patsubst %,$(LOCAL_PATH)/%,$(LOCAL_SRC_FILES))
-out_dir := $(OUT_DOCS)/$(LOCAL_MODULE)
-full_target := $(call doc-timestamp-for,$(LOCAL_MODULE))
-
-ifeq ($(LOCAL_DROIDDOC_SOURCE_PATH),)
-LOCAL_DROIDDOC_SOURCE_PATH := $(LOCAL_PATH)
-endif
-
-ifeq ($(LOCAL_DROIDDOC_CUSTOM_TEMPLATE_DIR),)
-LOCAL_DROIDDOC_CUSTOM_TEMPLATE_DIR := $(SRC_DROIDDOC_DIR)/$(LOCAL_DROIDDOC_CUSTOM_TEMPLATE_DIR)
-endif
-
-ifeq ($(LOCAL_DROIDDOC_ASSET_DIR),)
-LOCAL_DROIDDOC_ASSET_DIR := assets
-endif
-ifeq ($(LOCAL_DROIDDOC_CUSTOM_ASSET_DIR),)
-LOCAL_DROIDDOC_CUSTOM_ASSET_DIR := assets
-endif
-
-ifeq ($(LOCAL_IS_HOST_MODULE),true)
-$(full_target): PRIVATE_BOOTCLASSPATH :=
-full_java_libs := $(addprefix $(HOST_OUT_JAVA_LIBRARIES)/,\
-  $(addsuffix $(COMMON_JAVA_PACKAGE_SUFFIX),$(LOCAL_JAVA_LIBRARIES)))
-
-else
-
-ifneq ($(LOCAL_SDK_VERSION),)
-  ifeq ($(LOCAL_SDK_VERSION)$(TARGET_BUILD_APPS),current)
-    # Use android_stubs_current if LOCAL_SDK_VERSION is current and no TARGET_BUILD_APPS.
-    LOCAL_JAVA_LIBRARIES := android_stubs_current $(LOCAL_JAVA_LIBRARIES)
-    $(full_target): PRIVATE_BOOTCLASSPATH := $(call java-lib-files, android_stubs_current)
-  else ifeq ($(LOCAL_SDK_VERSION)$(TARGET_BUILD_APPS),system_current)
-    LOCAL_JAVA_LIBRARIES := android_system_stubs_current $(LOCAL_JAVA_LIBRARIES)
-    $(full_target): PRIVATE_BOOTCLASSPATH := $(call java-lib-files, android_system_stubs_current)
-  else ifeq ($(LOCAL_SDK_VERSION)$(TARGET_BUILD_APPS),test_current)
-    LOCAL_JAVA_LIBRARIES := android_test_stubs_current $(LOCAL_JAVA_LIBRARIES)
-    $(full_target): PRIVATE_BOOTCLASSPATH := $(call java-lib-files, android_test_stubs_current)
-  else ifeq ($(LOCAL_SDK_VERSION)$(TARGET_BUILD_APPS),core_current)
-    LOCAL_JAVA_LIBRARIES := core.current.stubs $(LOCAL_JAVA_LIBRARIES)
-    $(full_target): PRIVATE_BOOTCLASSPATH := $(call java-lib-files, core.current.stubs)
-  else
-    # TARGET_BUILD_APPS is set. Use the modules defined in prebuilts/sdk/Android.mk.
-    _module_name := $(call resolve-prebuilt-sdk-module,$(LOCAL_SDK_VERSION))
-    LOCAL_JAVA_LIBRARIES := $(_module_name) $(LOCAL_JAVA_LIBRARIES)
-    $(full_target): PRIVATE_BOOTCLASSPATH := $(call java-lib-files, $(_module_name))
-    _module_name :=
-  endif
-else
-  ifeq ($(LOCAL_NO_STANDARD_LIBRARIES),true)
-    LOCAL_JAVA_LIBRARIES := core-oj core-libart
-  else
-    LOCAL_JAVA_LIBRARIES := core-oj core-libart ext framework $(LOCAL_JAVA_LIBRARIES)
-  endif
-  $(full_target): PRIVATE_BOOTCLASSPATH := $(call java-lib-files, core-oj):$(call java-lib-files, core-libart)
-endif  # LOCAL_SDK_VERSION
-LOCAL_JAVA_LIBRARIES := $(sort $(LOCAL_JAVA_LIBRARIES))
-
-full_java_libs := $(call java-lib-files,$(LOCAL_JAVA_LIBRARIES)) $(LOCAL_CLASSPATH)
-endif # !LOCAL_IS_HOST_MODULE
-
-$(full_target): PRIVATE_CLASSPATH := $(call normalize-path-list,$(full_java_libs))
-
-intermediates.COMMON := $(call local-intermediates-dir,COMMON)
-
-$(full_target): PRIVATE_SOURCE_PATH := $(call normalize-path-list,$(LOCAL_DROIDDOC_SOURCE_PATH))
-$(full_target): PRIVATE_JAVA_FILES := $(filter %.java,$(full_src_files))
-$(full_target): PRIVATE_JAVA_FILES += $(addprefix $($(my_prefix)OUT_COMMON_INTERMEDIATES)/, $(filter %.java,$(LOCAL_INTERMEDIATE_SOURCES)))
-$(full_target): PRIVATE_JAVA_FILES += $(filter %.java,$(LOCAL_GENERATED_SOURCES))
-$(full_target): PRIVATE_SRCJARS := $(LOCAL_SRCJARS)
-$(full_target): PRIVATE_SOURCE_INTERMEDIATES_DIR := $(intermediates.COMMON)/src
-$(full_target): PRIVATE_SRCJAR_INTERMEDIATES_DIR := $(intermediates.COMMON)/srcjars
-$(full_target): PRIVATE_SRC_LIST_FILE := $(intermediates.COMMON)/droiddoc-src-list
-$(full_target): PRIVATE_SRCJAR_LIST_FILE := $(intermediates.COMMON)/droiddoc-srcjar-list
-
-ifneq ($(strip $(LOCAL_ADDITIONAL_JAVA_DIR)),)
-$(full_target): PRIVATE_ADDITIONAL_JAVA_DIR := $(LOCAL_ADDITIONAL_JAVA_DIR)
-endif
-
-$(full_target): PRIVATE_OUT_DIR := $(out_dir)
-$(full_target): PRIVATE_DROIDDOC_OPTIONS := $(LOCAL_DROIDDOC_OPTIONS)
-$(full_target): PRIVATE_STUB_OUT_DIR := $(LOCAL_DROIDDOC_STUB_OUT_DIR)
-
-# Lists the input files for the doc build into a text file
-# suitable for the @ syntax of javadoc.
-# $(1): the file to create
-# $(2): files to include
-# $(3): list of directories to search for java files in
-define prepare-doc-source-list
-$(hide) mkdir -p $(dir $(1))
-$(call dump-words-to-file, $(2), $(1))
-$(hide) for d in $(3) ; do find $$d -name '*.java' -and -not -name '.*' >> $(1) 2> /dev/null ; done ; true
-endef
-
-ifeq (a,b)
-$(full_target): PRIVATE_PROFILING_OPTIONS := \
-    -J-agentlib:jprofilerti=port=8849 -J-Xbootclasspath/a:/Applications/jprofiler5/bin/agent.jar
-endif
-
-
-ifneq ($(strip $(LOCAL_DROIDDOC_USE_STANDARD_DOCLET)),true)
-##
-##
-## droiddoc only
-##
-##
-
-droiddoc_templates := \
-    $(sort $(shell find $(LOCAL_DROIDDOC_CUSTOM_TEMPLATE_DIR) -type f $(if $(ALLOW_MISSING_DEPENDENCIES),2>/dev/null)))
-
-ifdef ALLOW_MISSING_DEPENDENCIES
-  ifndef droiddoc_templates
-    droiddoc_templates := $(LOCAL_DROIDDOC_CUSTOM_TEMPLATE_DIR)
-  endif
-endif
-
-droiddoc := \
-	$(HOST_JDK_TOOLS_JAR) \
-	$(HOST_OUT_JAVA_LIBRARIES)/doclava$(COMMON_JAVA_PACKAGE_SUFFIX)
-
-$(full_target): PRIVATE_DOCLETPATH := $(HOST_OUT_JAVA_LIBRARIES)/jsilver$(COMMON_JAVA_PACKAGE_SUFFIX):$(HOST_OUT_JAVA_LIBRARIES)/doclava$(COMMON_JAVA_PACKAGE_SUFFIX)
-$(full_target): PRIVATE_CURRENT_BUILD := -hdf page.build $(BUILD_ID)-$(BUILD_NUMBER_FROM_FILE)
-$(full_target): PRIVATE_CURRENT_TIME :=  -hdf page.now "$$($(DATE_FROM_FILE) "+%d %b %Y %k:%M")"
-$(full_target): PRIVATE_CUSTOM_TEMPLATE_DIR := $(LOCAL_DROIDDOC_CUSTOM_TEMPLATE_DIR)
-$(full_target): PRIVATE_IN_CUSTOM_ASSET_DIR := $(LOCAL_DROIDDOC_CUSTOM_TEMPLATE_DIR)/$(LOCAL_DROIDDOC_CUSTOM_ASSET_DIR)
-$(full_target): PRIVATE_OUT_ASSET_DIR := $(out_dir)/$(LOCAL_DROIDDOC_ASSET_DIR)
-$(full_target): PRIVATE_OUT_CUSTOM_ASSET_DIR := $(out_dir)/$(LOCAL_DROIDDOC_CUSTOM_ASSET_DIR)
-
-html_dir_files :=
-ifneq ($(strip $(LOCAL_DROIDDOC_HTML_DIR)),)
-$(full_target): PRIVATE_DROIDDOC_HTML_DIR := -htmldir $(LOCAL_PATH)/$(LOCAL_DROIDDOC_HTML_DIR)
-html_dir_files := $(sort $(shell find $(LOCAL_PATH)/$(LOCAL_DROIDDOC_HTML_DIR) -type f))
-else
-$(full_target): PRIVATE_DROIDDOC_HTML_DIR :=
-endif
-ifneq ($(strip $(LOCAL_ADDITIONAL_HTML_DIR)),)
-$(full_target): PRIVATE_ADDITIONAL_HTML_DIR := -htmldir2 $(LOCAL_PATH)/$(LOCAL_ADDITIONAL_HTML_DIR)
-else
-$(full_target): PRIVATE_ADDITIONAL_HTML_DIR :=
-endif
-
-# TODO: not clear if this is used any more
-$(full_target): PRIVATE_LOCAL_PATH := $(LOCAL_PATH)
-
-# TODO(tobiast): Clean this up once we move to -source 1.9.
-# OpenJDK 9 does not have the concept of a "boot classpath" so we should
-# then rename PRIVATE_BOOTCLASSPATH to PRIVATE_MODULE or similar. For now,
-# keep -bootclasspath here since it works in combination with -source 1.8.
-$(full_target): \
-        $(full_src_files) \
-        $(LOCAL_GENERATED_SOURCES) \
-        $(droiddoc_templates) \
-        $(droiddoc) \
-        $(html_dir_files) \
-        $(full_java_libs) \
-        $(ZIPSYNC) \
-        $(LOCAL_SRCJARS) \
-        $(LOCAL_ADDITIONAL_DEPENDENCIES)
-	@echo Docs droiddoc: $(PRIVATE_OUT_DIR)
-	$(hide) mkdir -p $(dir $@)
-	$(hide) rm -rf $(PRIVATE_STUB_OUT_DIR)
-	$(call prepare-doc-source-list,$(PRIVATE_SRC_LIST_FILE),$(PRIVATE_JAVA_FILES), \
-			$(PRIVATE_SOURCE_INTERMEDIATES_DIR) $(PRIVATE_ADDITIONAL_JAVA_DIR))
-	$(ZIPSYNC) -d $(PRIVATE_SRCJAR_INTERMEDIATES_DIR) -l $(PRIVATE_SRCJAR_LIST_FILE) -f "*.java" $(PRIVATE_SRCJARS)
-	$(hide) ( \
-		$(JAVADOC) \
-                -encoding UTF-8 \
-                -source 1.8 \
-                \@$(PRIVATE_SRC_LIST_FILE) \
-                \@$(PRIVATE_SRCJAR_LIST_FILE) \
-                -J-Xmx1600m \
-                -J-XX:-OmitStackTraceInFastThrow \
-                -XDignore.symbol.file \
-                $(PRIVATE_PROFILING_OPTIONS) \
-                -quiet \
-                -doclet com.google.doclava.Doclava \
-                -docletpath $(PRIVATE_DOCLETPATH) \
-                -templatedir $(PRIVATE_CUSTOM_TEMPLATE_DIR) \
-                $(PRIVATE_DROIDDOC_HTML_DIR) \
-                $(PRIVATE_ADDITIONAL_HTML_DIR) \
-                $(addprefix -bootclasspath ,$(PRIVATE_BOOTCLASSPATH)) \
-                $(addprefix -classpath ,$(PRIVATE_CLASSPATH)) \
-                -sourcepath $(PRIVATE_SOURCE_PATH) \
-                -d $(PRIVATE_OUT_DIR) \
-                $(PRIVATE_CURRENT_BUILD) $(PRIVATE_CURRENT_TIME) \
-                $(PRIVATE_DROIDDOC_OPTIONS) \
-                $(addprefix -stubs ,$(PRIVATE_STUB_OUT_DIR)) \
-        && touch -f $@ \
-    ) || (cat $(PRIVATE_SRC_LIST_FILE) $(PRIVATE_SRCJAR_LIST_FILE) && rm -rf $(PRIVATE_OUT_DIR) $(PRIVATE_SRC_LIST_FILE); exit 45)
-
-
-
-else
-##
-##
-## standard doclet only
-##
-##
-
-# For OpenJDK 9 we use --patch-module to define the core libraries code.
-# TODO(tobiast): Reorganize this when adding proper support for OpenJDK 9
-# modules. Here we treat all code in core libraries as being in java.base
-# to work around the OpenJDK 9 module system. http://b/62049770
-$(full_target): PRIVATE_BOOTCLASSPATH_ARG := --patch-module=java.base=$(PRIVATE_BOOTCLASSPATH)
-$(full_target): $(full_src_files) $(LOCAL_GENERATED_SOURCES) $(full_java_libs) $(ZIPSYNC) $(LOCAL_SRCJARS) $(LOCAL_ADDITIONAL_DEPENDENCIES)
-	@echo Docs javadoc: $(PRIVATE_OUT_DIR)
-	@mkdir -p $(dir $@)
-	$(call prepare-doc-source-list,$(PRIVATE_SRC_LIST_FILE),$(PRIVATE_JAVA_FILES), \
-			$(PRIVATE_SOURCE_INTERMEDIATES_DIR) $(PRIVATE_ADDITIONAL_JAVA_DIR))
-	$(ZIPSYNC) -d $(PRIVATE_SRCJAR_INTERMEDIATES_DIR) -l $(PRIVATE_SRCJAR_LIST_FILE) -f "*.java" $(PRIVATE_SRCJARS)
-	$(hide) ( \
-		$(JAVADOC) \
-                -encoding UTF-8 \
-                $(PRIVATE_DROIDDOC_OPTIONS) \
-                \@$(PRIVATE_SRC_LIST_FILE) \
-                \@$(PRIVATE_SRCJAR_LIST_FILE) \
-                -J-Xmx1024m \
-                -XDignore.symbol.file \
-                -Xdoclint:none \
-                $(PRIVATE_PROFILING_OPTIONS) \
-                $(addprefix -classpath ,$(PRIVATE_CLASSPATH)) \
-                $(PRIVATE_BOOTCLASSPATH_ARG) \
-                -sourcepath $(PRIVATE_SOURCE_PATH) \
-                -d $(PRIVATE_OUT_DIR) \
-                -quiet \
-        && touch -f $@ \
-    ) || (rm -rf $(PRIVATE_OUT_DIR) $(PRIVATE_SRC_LIST_FILE); exit 45)
-
-
-endif
-##
-##
-## Common to both droiddoc and javadoc
-##
-##
-
-
-ALL_DOCS += $(full_target)
-
-.PHONY: $(LOCAL_MODULE)-docs
-$(LOCAL_MODULE)-docs : $(full_target)
-
-ifeq ($(strip $(LOCAL_UNINSTALLABLE_MODULE)),)
-
-# Define a rule to create a zip of these docs.
-out_zip := $(OUT_DOCS)/$(LOCAL_MODULE)-docs.zip
-$(out_zip): PRIVATE_DOCS_DIR := $(out_dir)
-$(out_zip): $(full_target)
-	@echo Package docs: $@
-	@rm -f $@
-	@mkdir -p $(dir $@)
-	$(hide) ( F=$$(pwd)/$@ ; cd $(PRIVATE_DOCS_DIR) && zip -rqX $$F * )
-
-$(LOCAL_MODULE)-docs.zip : $(out_zip)
-.PHONY: $(LOCAL_MODULE)-docs.zip
-
-$(call dist-for-goals,docs,$(out_zip))
-
-endif
diff --git a/target/product/base_system.mk b/target/product/base_system.mk
index ef0d0c8..44c6976 100644
--- a/target/product/base_system.mk
+++ b/target/product/base_system.mk
@@ -109,6 +109,7 @@
     libaudiopolicyservice \
     libaudioutils \
     libbinder \
+    libbinder_ndk \
     libc \
     libcamera2ndk \
     libcamera_client \
diff --git a/tools/releasetools/ota_from_target_files.py b/tools/releasetools/ota_from_target_files.py
index 583af2d..eaba4df 100755
--- a/tools/releasetools/ota_from_target_files.py
+++ b/tools/releasetools/ota_from_target_files.py
@@ -285,6 +285,17 @@
     return self._fingerprint
 
   @property
+  def vendor_fingerprint(self):
+    if "vendor.build.prop" not in self.info_dict:
+      return None
+    vendor_build_prop = self.info_dict["vendor.build.prop"]
+    if "ro.vendor.build.fingerprint" in vendor_build_prop:
+      return vendor_build_prop["ro.vendor.build.fingerprint"]
+    if "ro.vendor.build.thumbprint" in vendor_build_prop:
+      return vendor_build_prop["ro.vendor.build.thumbprint"]
+    return None
+
+  @property
   def oem_props(self):
     return self._oem_props
 
@@ -706,11 +717,14 @@
   target_fp = target_info.fingerprint
   system_updated = source_fp != target_fp
 
-  source_fp_vendor = source_info.GetVendorBuildProp(
-      "ro.vendor.build.fingerprint")
-  target_fp_vendor = target_info.GetVendorBuildProp(
-      "ro.vendor.build.fingerprint")
-  vendor_updated = source_fp_vendor != target_fp_vendor
+  source_fp_vendor = source_info.vendor_fingerprint
+  target_fp_vendor = target_info.vendor_fingerprint
+  # vendor build fingerprints could be possibly blacklisted at build time. For
+  # such a case, we consider the vendor images being changed.
+  if source_fp_vendor is None or target_fp_vendor is None:
+    vendor_updated = True
+  else:
+    vendor_updated = source_fp_vendor != target_fp_vendor
 
   AddCompatibilityArchive(system_updated, vendor_updated)
 
diff --git a/tools/releasetools/test_ota_from_target_files.py b/tools/releasetools/test_ota_from_target_files.py
index c8e6750..8416af7 100644
--- a/tools/releasetools/test_ota_from_target_files.py
+++ b/tools/releasetools/test_ota_from_target_files.py
@@ -255,6 +255,23 @@
     self.assertRaises(common.ExternalError, target_info.GetVendorBuildProp,
                       'ro.build.nonexistent')
 
+  def test_vendor_fingerprint(self):
+    target_info = BuildInfo(self.TEST_INFO_DICT, None)
+    self.assertEqual('vendor-build-fingerprint',
+                     target_info.vendor_fingerprint)
+
+  def test_vendor_fingerprint_blacklisted(self):
+    target_info_dict = copy.deepcopy(self.TEST_INFO_DICT_USES_OEM_PROPS)
+    del target_info_dict['vendor.build.prop']['ro.vendor.build.fingerprint']
+    target_info = BuildInfo(target_info_dict, self.TEST_OEM_DICTS)
+    self.assertIsNone(target_info.vendor_fingerprint)
+
+  def test_vendor_fingerprint_without_vendor_build_prop(self):
+    target_info_dict = copy.deepcopy(self.TEST_INFO_DICT_USES_OEM_PROPS)
+    del target_info_dict['vendor.build.prop']
+    target_info = BuildInfo(target_info_dict, self.TEST_OEM_DICTS)
+    self.assertIsNone(target_info.vendor_fingerprint)
+
   def test_WriteMountOemScript(self):
     target_info = BuildInfo(self.TEST_INFO_DICT_USES_OEM_PROPS,
                             self.TEST_OEM_DICTS)