Support to build with AAPT2

To build with AAPT2, set "USE_AAPT2=true".
TODO: Support split apks and generated resources from other than renderscript.

Bug: 25958912
Change-Id: I19b1a038824ce5b2a3d3ffadbce3173c845193fc
diff --git a/core/aapt2.mk b/core/aapt2.mk
new file mode 100644
index 0000000..d064d5f
--- /dev/null
+++ b/core/aapt2.mk
@@ -0,0 +1,76 @@
+######################################
+# Compile resource with AAPT2
+# Input variables:
+# full_android_manifest,
+# my_res_resources, my_overlay_resources, my_aapt_characteristics,
+# my_compiled_res_base_dir, rs_generated_res_dir, my_res_package,
+# R_file_stamp, proguard_options_file
+# Output variables:
+# my_res_resources_flat, my_overlay_resources_flat,
+# my_generated_resources_flata
+#
+######################################
+
+
+# Compile all the resource files.
+my_res_resources_flat := \
+  $(foreach r, $(my_res_resources),\
+    $(eval o := $(call aapt2-compiled-resource-out-file,$(r),$(my_compiled_res_base_dir)))\
+    $(eval $(call aapt2-compile-one-resource-file-rule,$(r),$(o)))\
+    $(o))
+
+my_overlay_resources_flat := \
+  $(foreach r, $(my_overlay_resources),\
+    $(eval o := $(call aapt2-compiled-resource-out-file,$(r),$(my_compiled_res_base_dir)))\
+    $(eval $(call aapt2-compile-one-resource-file-rule,$(r),$(o)))\
+    $(o))
+
+my_generated_resources_flata :=
+# Compile generated resources
+ifneq ($(rs_generated_res_dir),)
+rs_gen_resource_flata := $(my_compiled_res_base_dir)/renderscript_gen_res.flata
+$(rs_gen_resource_flata): PRIVATE_SOURCE_RES_DIR := $(rs_generated_res_dir)
+$(rs_gen_resource_flata) : $(RenderScript_file_stamp)
+	@echo "AAPT2 compile $@ <- $(PRIVATE_SOURCE_RES_DIR)"
+	$(call aapt2-compile-one-resource-dir)
+
+my_generated_resources_flata += $(rs_gen_resource_flata)
+endif
+
+$(my_res_resources_flat) $(my_overlay_resources_flat) $(my_generated_resources_flata): \
+  PRIVATE_AAPT2_CFLAGS := $(addprefix --product ,$(my_aapt_characteristics))
+
+# Link the static library resource packages.
+my_static_library_resources := $(foreach l, $(LOCAL_STATIC_JAVA_LIBRARIES),\
+  $(call intermediates-dir-for,JAVA_LIBRARIES,$(l),,COMMON)/library-res.flata)
+
+$(my_res_package): PRIVATE_RES_FLAT := $(my_res_resources_flat)
+$(my_res_package): PRIVATE_OVERLAY_FLAT := $(my_overlay_resources_flat) $(my_generated_resources_flata) $(my_static_library_resources)
+$(my_res_package): PRIVATE_PROGUARD_OPTIONS_FILE := $(proguard_options_file)
+$(my_res_package) : $(full_android_manifest)
+$(my_res_package) : $(my_res_resources_flat) $(my_overlay_resources_flat) \
+  $(my_generated_resources_flata) $(my_static_library_resources) \
+  $(AAPT2)
+	@echo "AAPT2 link $@"
+	$(call aapt2-link)
+
+$(R_file_stamp) : $(my_res_package) | $(ACP)
+	@echo "target R.java/Manifest.java: $(PRIVATE_MODULE) ($@)"
+	@rm -rf $@ && mkdir -p $(dir $@)
+	$(call find-generated-R.java)
+
+$(proguard_options_file) : $(my_res_package)
+
+resource_export_package :=
+ifdef LOCAL_EXPORT_PACKAGE_RESOURCES
+# Put this module's resources into a PRODUCT-agnositc package that
+# other packages can use to build their own PRODUCT-agnostic R.java (etc.)
+# files.
+resource_export_package := $(intermediates.COMMON)/package-export.apk
+$(R_file_stamp) : $(resource_export_package)
+
+$(resource_export_package) : $(my_res_package) | $(ACP)
+	@echo "target Export Resources: $(PRIVATE_MODULE) $(@)"
+	$(copy-file-to-new-target)
+
+endif
diff --git a/core/android_manifest.mk b/core/android_manifest.mk
index 582bad4..b945ea9 100644
--- a/core/android_manifest.mk
+++ b/core/android_manifest.mk
@@ -22,9 +22,12 @@
 my_full_libs_manifest_files += $(foreach lib, $(LOCAL_STATIC_JAVA_AAR_LIBRARIES),\
   $(call intermediates-dir-for,JAVA_LIBRARIES,$(lib),,COMMON)/aar/AndroidManifest.xml)
 
+# With USE_AAPT2, we'll link in the built resource from the AAR.
+ifndef USE_AAPT2
 LOCAL_RESOURCE_DIR += $(foreach lib, $(LOCAL_STATIC_JAVA_AAR_LIBRARIES),\
   $(call intermediates-dir-for,JAVA_LIBRARIES,$(lib),,COMMON)/aar/res)
-endif
+endif  # USE_AAPT2
+endif  # LOCAL_STATIC_JAVA_AAR_LIBRARIES
 
 # Set up rules to merge library manifest files
 ifdef my_full_libs_manifest_files
diff --git a/core/config.mk b/core/config.mk
index e5de5e9..7eb81ed 100644
--- a/core/config.mk
+++ b/core/config.mk
@@ -403,6 +403,7 @@
 ACP := $(HOST_OUT_EXECUTABLES)/acp
 AIDL := $(HOST_OUT_EXECUTABLES)/aidl
 AAPT := $(HOST_OUT_EXECUTABLES)/aapt
+AAPT2 := $(HOST_OUT_EXECUTABLES)/aapt2
 ZIPALIGN := $(HOST_OUT_EXECUTABLES)/zipalign
 SIGNAPK_JAR := $(HOST_OUT_JAVA_LIBRARIES)/signapk$(COMMON_JAVA_PACKAGE_SUFFIX)
 SIGNAPK_JNI_LIBRARY_PATH := $(HOST_OUT_SHARED_LIBRARIES)
@@ -422,6 +423,7 @@
 ACP := $(prebuilt_sdk_tools_bin)/acp
 AIDL := $(prebuilt_sdk_tools_bin)/aidl
 AAPT := $(prebuilt_sdk_tools_bin)/aapt
+AAPT2 := $(prebuilt_sdk_tools_bin)/aapt2
 ZIPALIGN := $(prebuilt_sdk_tools_bin)/zipalign
 SIGNAPK_JAR := $(prebuilt_sdk_tools)/lib/signapk$(COMMON_JAVA_PACKAGE_SUFFIX)
 # Use 64-bit libraries unconditionally because 32-bit JVMs are no longer supported
diff --git a/core/definitions.mk b/core/definitions.mk
index 2105df3..8f5fd11 100644
--- a/core/definitions.mk
+++ b/core/definitions.mk
@@ -1726,6 +1726,78 @@
     --skip-symbols-without-default-localization
 endef
 
+# Search for generated R.java/Manifest.java, copy the found R.java as $@.
+# Also copy them to a central 'R' directory to make it easier to add the files to an IDE.
+define find-generated-R.java
+$(hide) for GENERATED_MANIFEST_FILE in `find $(PRIVATE_SOURCE_INTERMEDIATES_DIR) \
+  -name Manifest.java 2> /dev/null`; do \
+    dir=`awk '/package/{gsub(/\./,"/",$$2);gsub(/;/,"",$$2);print $$2;exit}' $$GENERATED_MANIFEST_FILE`; \
+    mkdir -p $(TARGET_COMMON_OUT_ROOT)/R/$$dir; \
+    $(ACP) -fp $$GENERATED_MANIFEST_FILE $(TARGET_COMMON_OUT_ROOT)/R/$$dir; \
+  done;
+$(hide) for GENERATED_R_FILE in `find $(PRIVATE_SOURCE_INTERMEDIATES_DIR) \
+  -name R.java 2> /dev/null`; do \
+    dir=`awk '/package/{gsub(/\./,"/",$$2);gsub(/;/,"",$$2);print $$2;exit}' $$GENERATED_R_FILE`; \
+    mkdir -p $(TARGET_COMMON_OUT_ROOT)/R/$$dir; \
+    $(ACP) -fp $$GENERATED_R_FILE $(TARGET_COMMON_OUT_ROOT)/R/$$dir \
+      || exit 31; \
+    $(ACP) -fp $$GENERATED_R_FILE $@ || exit 32; \
+  done;
+@# Ensure that the target file is always created, i.e. also in case we did not
+@# enter the GENERATED_R_FILE-loop above. This avoids unnecessary rebuilding.
+$(hide) touch $@
+endef
+
+###########################################################
+# AAPT2 compilation and link
+###########################################################
+define aapt2-compile-one-resource-file
+@mkdir -p $(dir $@)
+$(hide) $(AAPT2) compile -o $(dir $@) $(PRIVATE_AAPT2_CFLAGS) --legacy $<
+endef
+
+define aapt2-compile-one-resource-dir
+@mkdir -p $(dir $@)
+$(hide) $(AAPT2) compile -o $@ --dir $(PRIVATE_SOURCE_RES_DIR) \
+  $(PRIVATE_AAPT2_CFLAGS) --legacy
+endef
+
+# Set up rule to compile one resource file with aapt2.
+# Must be called with $(eval).
+# $(1): the source file
+# $(2): the output file
+define aapt2-compile-one-resource-file-rule
+$(2) : $(1) $(AAPT2)
+	@echo "AAPT2 compile $$@ <- $$<"
+	$$(call aapt2-compile-one-resource-file)
+endef
+
+# Convert input resource file path to output file path.
+# values-[config]/<file>.xml -> values-[config]_<file>.arsc.flat;
+# For other resource file, just replace the last "/" with "_" and
+# add .flat extension.
+#
+# $(1): the input resource file path
+# $(2): the base dir of the output file path
+# Returns: the compiled output file path
+define aapt2-compiled-resource-out-file
+$(eval _p_w := $(strip $(subst /,$(space),$(dir $(1)))))$(2)/$(subst $(space),/,$(_p_w))_$(if $(filter values%,$(lastword $(_p_w))),$(patsubst %.xml,%.arsc,$(notdir $(1))),$(notdir $(1))).flat
+endef
+
+define aapt2-link
+$(hide) $(AAPT2) link -o $@ \
+  $(PRIVATE_AAPT_FLAGS) \
+  $(addprefix --manifest ,$(PRIVATE_ANDROID_MANIFEST)) \
+  $(addprefix -I ,$(PRIVATE_AAPT_INCLUDES)) \
+  $(addprefix --java ,$(PRIVATE_SOURCE_INTERMEDIATES_DIR)) \
+  $(addprefix --proguard ,$(PRIVATE_PROGUARD_OPTIONS_FILE)) \
+  $(addprefix --min-sdk-version ,$(PRIVATE_DEFAULT_APP_TARGET_SDK)) \
+  $(addprefix --target-sdk-version ,$(PRIVATE_DEFAULT_APP_TARGET_SDK)) \
+  $(addprefix -R , $(PRIVATE_OVERLAY_FLAT)) \
+  $(PRIVATE_RES_FLAT)
+endef
+
+###########################################################
 xlint_unchecked := -Xlint:unchecked
 
 # emit-line, <word list>, <output file>
diff --git a/core/java.mk b/core/java.mk
index 70ff1a1..28128da 100644
--- a/core/java.mk
+++ b/core/java.mk
@@ -145,6 +145,7 @@
 # Because names of the java files from RenderScript are unknown until the
 # .rs file(s) are compiled, we have to depend on a timestamp file.
 RenderScript_file_stamp :=
+rs_generated_res_dir :=
 rs_compatibility_jni_libs :=
 ifneq ($(renderscript_sources),)
 renderscript_sources_fullpath := $(addprefix $(LOCAL_PATH)/, $(renderscript_sources))
@@ -277,7 +278,8 @@
 
 LOCAL_INTERMEDIATE_TARGETS += $(RenderScript_file_stamp)
 # Make sure the generated resource will be added to the apk.
-LOCAL_RESOURCE_DIR := $(LOCAL_INTERMEDIATE_SOURCE_DIR)/renderscript/res $(LOCAL_RESOURCE_DIR)
+rs_generated_res_dir := $(renderscript_intermediate.COMMON)/res
+LOCAL_RESOURCE_DIR := $(rs_generated_res_dir) $(LOCAL_RESOURCE_DIR)
 endif
 
 
diff --git a/core/package_internal.mk b/core/package_internal.mk
index ecb6913..30022bc 100644
--- a/core/package_internal.mk
+++ b/core/package_internal.mk
@@ -57,6 +57,9 @@
 endif
 LOCAL_MODULE_CLASS := APPS
 
+intermediates := $(call local-intermediates-dir)
+intermediates.COMMON := $(call local-intermediates-dir,COMMON)
+
 #################################
 include $(BUILD_SYSTEM)/configure_local_jack.mk
 #################################
@@ -112,6 +115,32 @@
 need_compile_asset := true
 endif
 
+ifdef USE_AAPT2
+# In aapt2 the last takes precedence.
+my_resource_dirs := $(call reverse-list,$(LOCAL_RESOURCE_DIR))
+my_res_resources :=
+my_overlay_resources :=
+# Treat all but the first directory as overlays.
+my_overlay_resources := $(strip \
+  $(foreach d,$(wordlist 2,999,$(my_resource_dirs)),\
+    $(addprefix $(d)/, \
+        $(call find-subdir-assets,$(d)))))
+
+my_res_dir := $(firstword $(my_resource_dirs))
+my_res_resources := $(strip \
+    $(addprefix $(my_res_dir)/, \
+        $(call find-subdir-assets,$(my_res_dir))))
+
+all_resources := $(strip $(my_res_resources) $(my_overlay_resources))
+
+# The linked resource package.
+my_res_package := $(intermediates)/package-res.apk
+LOCAL_INTERMEDIATE_TARGETS += $(my_res_package)
+
+# Always run aapt2
+need_compile_res := true
+
+else  # USE_AAPT2
 all_resources := $(strip \
     $(foreach dir, $(LOCAL_RESOURCE_DIR), \
       $(addprefix $(dir)/, \
@@ -121,13 +150,14 @@
        ) \
      ))
 
+endif  # USE_AAPT2
+
 ifneq ($(all_resources),)
   need_compile_res := true
 endif
 
 all_res_assets := $(strip $(all_assets) $(all_resources))
 
-intermediates.COMMON := $(call local-intermediates-dir,COMMON)
 
 # If no assets or resources were found, clear the directory variables so
 # we don't try to build them.
@@ -272,6 +302,11 @@
 endif  # LOCAL_DATA_BINDING
 
 ifeq ($(need_compile_res),true)
+ifdef USE_AAPT2
+my_aapt_characteristics := $(TARGET_AAPT_CHARACTERISTICS)
+my_compiled_res_base_dir := $(intermediates)/flat-res
+include $(BUILD_SYSTEM)/aapt2.mk
+else  # USE_AAPT2
 
 # Since we don't know where the real R.java file is going to end up,
 # we need to use another file to stand in its place.  We'll just
@@ -289,23 +324,7 @@
 	@echo "target R.java/Manifest.java: $(PRIVATE_MODULE) ($@)"
 	@rm -rf $@ && mkdir -p $(dir $@)
 	$(create-resource-java-files)
-	$(hide) for GENERATED_MANIFEST_FILE in `find $(PRIVATE_SOURCE_INTERMEDIATES_DIR) \
-					-name Manifest.java 2> /dev/null`; do \
-		dir=`awk '/package/{gsub(/\./,"/",$$2);gsub(/;/,"",$$2);print $$2;exit}' $$GENERATED_MANIFEST_FILE`; \
-		mkdir -p $(TARGET_COMMON_OUT_ROOT)/R/$$dir; \
-		$(ACP) -fp $$GENERATED_MANIFEST_FILE $(TARGET_COMMON_OUT_ROOT)/R/$$dir; \
-	done;
-	$(hide) for GENERATED_R_FILE in `find $(PRIVATE_SOURCE_INTERMEDIATES_DIR) \
-					-name R.java 2> /dev/null`; do \
-		dir=`awk '/package/{gsub(/\./,"/",$$2);gsub(/;/,"",$$2);print $$2;exit}' $$GENERATED_R_FILE`; \
-		mkdir -p $(TARGET_COMMON_OUT_ROOT)/R/$$dir; \
-		$(ACP) -fp $$GENERATED_R_FILE $(TARGET_COMMON_OUT_ROOT)/R/$$dir \
-			|| exit 31; \
-		$(ACP) -fp $$GENERATED_R_FILE $@ || exit 32; \
-	done;
-	@# Ensure that the target file is always created, i.e. also in case we did not
-	@# enter the GENERATED_R_FILE-loop above. This avoids unnecessary rebuilding.
-	$(hide) touch $@
+	$(call find-generated-R.java)
 
 $(proguard_options_file): $(R_file_stamp)
 
@@ -327,6 +346,8 @@
 	$(add-assets-to-package)
 endif
 
+endif  # USE_AAPT2
+
 # Other modules should depend on the BUILT module if
 # they want to use this module's R.java file.
 $(LOCAL_BUILT_MODULE): $(R_file_stamp)
@@ -384,10 +405,13 @@
     $(framework_res_package_export_deps) \
     $(foreach lib,$(LOCAL_RES_LIBRARIES),\
         $(call intermediates-dir-for,APPS,$(lib),,COMMON)/src/R.stamp)
-
 $(resource_export_package) $(R_file_stamp) $(LOCAL_BUILT_MODULE): $(all_library_res_package_export_deps)
 $(LOCAL_INTERMEDIATE_TARGETS): \
     PRIVATE_AAPT_INCLUDES := $(all_library_res_package_exports)
+
+ifdef USE_AAPT2
+$(my_res_package) : $(all_library_res_package_export_deps)
+endif
 endif # LOCAL_NO_STANDARD_LIBRARIES
 
 ifneq ($(full_classes_jar),)
@@ -436,7 +460,6 @@
     $(LOCAL_ADDITIONAL_CERTIFICATES), $(c).x509.pem $(c).pk8)
 
 # Define the rule to build the actual package.
-$(LOCAL_BUILT_MODULE): $(AAPT)
 # PRIVATE_JNI_SHARED_LIBRARIES is a list of <abi>:<path_of_built_lib>.
 $(LOCAL_BUILT_MODULE): PRIVATE_JNI_SHARED_LIBRARIES := $(jni_shared_libraries_with_abis)
 # PRIVATE_JNI_SHARED_LIBRARIES_ABI is a list of ABI names.
@@ -457,8 +480,24 @@
 endif
 endif
 $(LOCAL_BUILT_MODULE): PRIVATE_DONT_DELETE_JAR_DIRS := $(LOCAL_DONT_DELETE_JAR_DIRS)
-$(LOCAL_BUILT_MODULE): $(all_res_assets) $(jni_shared_libraries) $(full_android_manifest)
+$(LOCAL_BUILT_MODULE) : $(jni_shared_libraries)
+ifdef USE_AAPT2
+$(LOCAL_BUILT_MODULE): PRIVATE_RES_PACKAGE := $(my_res_package)
+$(LOCAL_BUILT_MODULE) : $(my_res_package) $(AAPT2) | $(ACP)
+else
+$(LOCAL_BUILT_MODULE) : $(all_res_assets) $(full_android_manifest) $(AAPT)
+endif
 	@echo "target Package: $(PRIVATE_MODULE) ($@)"
+ifdef USE_AAPT2
+ifdef LOCAL_JACK_ENABLED
+	$(call copy-file-to-new-target)
+else
+	@# TODO: implement merge-two-packages.
+	$(if $(PRIVATE_SOURCE_ARCHIVE),\
+	  $(call merge-two-packages,$(PRIVATE_RES_PACKAGE) $(PRIVATE_SOURCE_ARCHIVE),$@),
+	  $(call copy-file-to-new-target))
+endif
+else  # USE_AAPT2
 ifdef LOCAL_JACK_ENABLED
 	$(create-empty-package)
 else
@@ -467,6 +506,7 @@
 	  $(create-empty-package))
 endif
 	$(add-assets-to-package)
+endif  # USE_AAPT2
 ifneq ($(jni_shared_libraries),)
 	$(add-jni-shared-libs-to-package)
 endif
diff --git a/core/prebuilt_internal.mk b/core/prebuilt_internal.mk
index 601a79c..dd8ff1c 100644
--- a/core/prebuilt_internal.mk
+++ b/core/prebuilt_internal.mk
@@ -296,11 +296,12 @@
 
 $(common_classes_jar) $(common_javalib_jar): PRIVATE_MODULE := $(LOCAL_MODULE)
 
-ifneq ($(filter %.aar, $(my_prebuilt_src_file)),)
+my_src_aar := $(filter %.aar, $(my_prebuilt_src_file))
+ifneq ($(my_src_aar),)
 # This is .aar file, archive of classes.jar and Android resources.
 my_src_jar := $(intermediates.COMMON)/aar/classes.jar
 
-$(my_src_jar) : $(my_prebuilt_src_file)
+$(my_src_jar) : $(my_src_aar)
 	$(hide) rm -rf $(dir $@) && mkdir -p $(dir $@)
 	$(hide) unzip -qo -d $(dir $@) $<
 	# Make sure the extracted classes.jar has a new timestamp.
@@ -318,6 +319,26 @@
 
 $(call define-jar-to-toc-rule, $(common_classes_jar))
 
+ifdef USE_AAPT2
+my_library_resources := $(intermediates.COMMON)/library-res.flata
+ifneq ($(my_src_aar),)
+# Compile the AAR resources to a .flata.
+$(my_library_resources): PRIVATE_SOURCE_RES_DIR := $(intermediates.COMMON)/aar/res
+$(my_library_resources) : $(my_src_jar)
+	@echo "AAPT2 compile AAR $@ <- $(PRIVATE_SOURCE_RES_DIR)"
+	$(call aapt2-compile-one-resource-dir)
+else  # $(my_src_aar)
+# Create an empty packag for prebuilt static Java library.
+# TODO: support compiled resources inside a prebuilt static Java library.
+$(my_library_resources): PRIVATE_RES_DIR := $(intermediates.COMMON)/flat-res/res
+$(my_library_resources) :
+	@echo "Create empty library resources $@"
+	@rm -rf $@ && mkdir -p $(dir $@) $(PRIVATE_RES_DIR)
+	$(hide) cd $(dir $(PRIVATE_RES_DIR)) && zip -qrX $(abspath $@) $(notdir $(PRIVATE_RES_DIR))
+endif  # $(my_src_aar)
+# Make sure my_library_resources is created when you run mm/mmm.
+$(built_module) : $(my_library_resources)
+endif  # USE_AAPT2
 # make sure the classes.jar and javalib.jar are built before $(LOCAL_BUILT_MODULE)
 $(built_module) : $(common_javalib_jar)
 endif # TARGET JAVA_LIBRARIES
diff --git a/core/static_java_library.mk b/core/static_java_library.mk
index c1c90d9..6efeb35 100644
--- a/core/static_java_library.mk
+++ b/core/static_java_library.mk
@@ -27,6 +27,13 @@
 include $(BUILD_SYSTEM)/configure_local_jack.mk
 #################################
 
+intermediates.COMMON := $(call local-intermediates-dir,COMMON)
+
+my_res_package :=
+# A zip file that apps can link with aapt2
+# We need my_library_resources as dependency even if a library doesn't have resource.
+my_library_resources := $(intermediates.COMMON)/library-res.flata
+
 # Hack to build static Java library with Android resource
 # See bug 5714516
 all_resources :=
@@ -34,6 +41,7 @@
 # A static Java library needs to explicily set LOCAL_RESOURCE_DIR.
 ifdef LOCAL_RESOURCE_DIR
 need_compile_res := true
+
 all_resources := $(strip \
     $(foreach dir, $(LOCAL_RESOURCE_DIR), \
       $(addprefix $(dir)/, \
@@ -56,7 +64,6 @@
 
 proguard_options_file :=
 
-intermediates.COMMON := $(call local-intermediates-dir,COMMON)
 ifneq ($(LOCAL_PROGUARD_ENABLED),custom)
   proguard_options_file := $(intermediates.COMMON)/proguard_options
 endif
@@ -70,6 +77,18 @@
 LOCAL_JACK_PROGUARD_FLAGS := $(addprefix -include ,$(proguard_options_file)) $(LOCAL_JACK_PROGUARD_FLAGS)
 endif # LOCAL_JACK_ENABLED
 
+R_file_stamp := $(intermediates.COMMON)/src/R.stamp
+LOCAL_INTERMEDIATE_TARGETS += $(R_file_stamp)
+
+ifdef USE_AAPT2
+# For library we treat all the resource equal with no overlay.
+my_res_resources := $(all_resources)
+my_overlay_resources :=
+# For libraries put everything in the COMMON intermediate directory.
+my_res_package := $(intermediates.COMMON)/package-res.apk
+
+LOCAL_INTERMEDIATE_TARGETS += $(my_res_package)
+endif  # USE_AAPT2
 endif  # LOCAL_RESOURCE_DIR
 
 all_res_assets := $(all_resources)
@@ -77,8 +96,6 @@
 include $(BUILD_SYSTEM)/java_library.mk
 
 ifeq (true,$(need_compile_res))
-R_file_stamp := $(LOCAL_INTERMEDIATE_SOURCE_DIR)/R.stamp
-
 include $(BUILD_SYSTEM)/android_manifest.mk
 
 LOCAL_SDK_RES_VERSION:=$(strip $(LOCAL_SDK_RES_VERSION))
@@ -102,29 +119,41 @@
 endif
 endif
 
-$(R_file_stamp): PRIVATE_MODULE := $(LOCAL_MODULE)
 # add --non-constant-id to prevent inlining constants.
 # AAR needs text symbol file R.txt.
-$(R_file_stamp): PRIVATE_AAPT_FLAGS := $(LOCAL_AAPT_FLAGS) --non-constant-id --output-text-symbols $(LOCAL_INTERMEDIATE_SOURCE_DIR)
-$(R_file_stamp): PRIVATE_SOURCE_INTERMEDIATES_DIR := $(LOCAL_INTERMEDIATE_SOURCE_DIR)
-$(R_file_stamp): PRIVATE_ANDROID_MANIFEST := $(full_android_manifest)
-$(R_file_stamp): PRIVATE_RESOURCE_PUBLICS_OUTPUT := $(intermediates.COMMON)/public_resources.xml
-$(R_file_stamp): PRIVATE_RESOURCE_DIR := $(LOCAL_RESOURCE_DIR)
-$(R_file_stamp): PRIVATE_AAPT_INCLUDES := $(framework_res_package_export)
-ifneq (,$(filter-out current system_current test_current, $(LOCAL_SDK_VERSION)))
-$(R_file_stamp): PRIVATE_DEFAULT_APP_TARGET_SDK := $(LOCAL_SDK_VERSION)
+ifdef USE_AAPT2
+$(LOCAL_INTERMEDIATE_TARGETS): PRIVATE_AAPT_FLAGS := $(LOCAL_AAPT_FLAGS) --non-final-ids
 else
-$(R_file_stamp): PRIVATE_DEFAULT_APP_TARGET_SDK := $(DEFAULT_APP_TARGET_SDK)
+$(LOCAL_INTERMEDIATE_TARGETS): PRIVATE_AAPT_FLAGS := $(LOCAL_AAPT_FLAGS) --non-constant-id --output-text-symbols $(LOCAL_INTERMEDIATE_SOURCE_DIR)
 endif
-$(R_file_stamp): PRIVATE_ASSET_DIR :=
-$(R_file_stamp): PRIVATE_PROGUARD_OPTIONS_FILE := $(proguard_options_file)
-$(R_file_stamp): PRIVATE_MANIFEST_PACKAGE_NAME :=
-$(R_file_stamp): PRIVATE_MANIFEST_INSTRUMENTATION_FOR :=
+$(LOCAL_INTERMEDIATE_TARGETS): PRIVATE_SOURCE_INTERMEDIATES_DIR := $(LOCAL_INTERMEDIATE_SOURCE_DIR)
+$(LOCAL_INTERMEDIATE_TARGETS): PRIVATE_ANDROID_MANIFEST := $(full_android_manifest)
+$(LOCAL_INTERMEDIATE_TARGETS): PRIVATE_RESOURCE_PUBLICS_OUTPUT := $(intermediates.COMMON)/public_resources.xml
+$(LOCAL_INTERMEDIATE_TARGETS): PRIVATE_RESOURCE_DIR := $(LOCAL_RESOURCE_DIR)
+$(LOCAL_INTERMEDIATE_TARGETS): PRIVATE_AAPT_INCLUDES := $(framework_res_package_export)
+ifneq (,$(filter-out current system_current test_current, $(LOCAL_SDK_VERSION)))
+$(LOCAL_INTERMEDIATE_TARGETS): PRIVATE_DEFAULT_APP_TARGET_SDK := $(LOCAL_SDK_VERSION)
+else
+$(LOCAL_INTERMEDIATE_TARGETS): PRIVATE_DEFAULT_APP_TARGET_SDK := $(DEFAULT_APP_TARGET_SDK)
+endif
+$(LOCAL_INTERMEDIATE_TARGETS): PRIVATE_ASSET_DIR :=
+$(LOCAL_INTERMEDIATE_TARGETS): PRIVATE_PROGUARD_OPTIONS_FILE := $(proguard_options_file)
+$(LOCAL_INTERMEDIATE_TARGETS): PRIVATE_MANIFEST_PACKAGE_NAME :=
+$(LOCAL_INTERMEDIATE_TARGETS): PRIVATE_MANIFEST_INSTRUMENTATION_FOR :=
 
+ifdef USE_AAPT2
+# For libraries don't use any product specific flags.
+my_aapt_characteristics :=
+# One more level with name res so we can zip up the flat resources that can be linked by apps.
+my_compiled_res_base_dir := $(intermediates.COMMON)/flat-res/res
+include $(BUILD_SYSTEM)/aapt2.mk
+$(my_res_package) : $(framework_res_package_export_deps)
+else
 $(R_file_stamp) : $(all_resources) $(full_android_manifest) $(AAPT) $(framework_res_package_export_deps)
 	@echo "target R.java/Manifest.java: $(PRIVATE_MODULE) ($@)"
 	$(create-resource-java-files)
 	$(hide) find $(PRIVATE_SOURCE_INTERMEDIATES_DIR) -name R.java | xargs cat > $@
+endif  # USE_AAPT2
 
 $(LOCAL_BUILT_MODULE): $(R_file_stamp)
 ifdef LOCAL_JACK_ENABLED
@@ -153,9 +182,20 @@
 
 # Register the aar file.
 ALL_MODULES.$(LOCAL_MODULE).AAR := $(built_aar)
-
 endif  # need_compile_res
 
+ifdef USE_AAPT2
+# If a static Java library has no resources, create empty package apps can depend on.
+$(my_library_resources): PRIVATE_RES_DIR := $(intermediates.COMMON)/flat-res/res
+$(my_library_resources) : $(my_res_package)
+	@echo "Package static library resources $@"
+	@rm -rf $@ && mkdir -p $(dir $@) $(PRIVATE_RES_DIR)
+	$(hide) cd $(dir $(PRIVATE_RES_DIR)) && zip -qrX $(abspath $@) $(notdir $(PRIVATE_RES_DIR))
+
+# Make sure my_library_resources is created when you run mm/mmm.
+$(LOCAL_BUILT_MODULE) : $(my_library_resources)
+endif  # USE_AAPT2
+
 # Reset internal variables.
 all_res_assets :=
 LOCAL_IS_STATIC_JAVA_LIBRARY :=