diff --git a/CleanSpec.mk b/CleanSpec.mk
index 64d84e3..9cab929 100644
--- a/CleanSpec.mk
+++ b/CleanSpec.mk
@@ -354,7 +354,7 @@
 $(call add-clean-step, rm -rf $(PRODUCT_OUT)/root/default.prop)
 $(call add-clean-step, rm -rf $(PRODUCT_OUT)/recovery/root/default.prop)
 
-# Change PLATFORM_VERSION from MNC to M
+# New York, New York!
 $(call add-clean-step, rm -rf $(PRODUCT_OUT)/system/build.prop)
 $(call add-clean-step, rm -rf $(PRODUCT_OUT)/system/app/*)
 $(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/APPS/*)
@@ -364,13 +364,13 @@
 $(call add-clean-step, rm -rf $(PRODUCT_OUT)/system/app/*)
 $(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/APPS/*)
 
-# 23 is becoming more alive!!!
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/system/build.prop)
+
+# Change PLATFORM_VERSION from NYC to N
 $(call add-clean-step, rm -rf $(PRODUCT_OUT)/system/build.prop)
 $(call add-clean-step, rm -rf $(PRODUCT_OUT)/system/app/*)
 $(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/APPS/*)
 
-$(call add-clean-step, rm -rf $(PRODUCT_OUT)/system/build.prop)
-
 # ************************************************
 # NEWER CLEAN STEPS MUST BE AT THE END OF THE LIST
 # ************************************************
diff --git a/core/Makefile b/core/Makefile
index 73f933e..42d92c9 100644
--- a/core/Makefile
+++ b/core/Makefile
@@ -498,7 +498,6 @@
 INTERNAL_BOOTIMAGE_ARGS += --ramdisk $(INSTALLED_RAMDISK_TARGET)
 endif
 
-
 INTERNAL_BOOTIMAGE_FILES := $(filter-out --%,$(INTERNAL_BOOTIMAGE_ARGS))
 
 BOARD_KERNEL_CMDLINE := $(strip $(BOARD_KERNEL_CMDLINE))
diff --git a/core/base_rules.mk b/core/base_rules.mk
index 7e33660..dbcd563 100644
--- a/core/base_rules.mk
+++ b/core/base_rules.mk
@@ -304,7 +304,7 @@
   LOCAL_ACP_UNAVAILABLE := $(strip $(HOST_ACP_UNAVAILABLE))
 endif
 
-ifndef LOCAL_UNINSTALLABLE_MODULE
+ifneq (true,$(LOCAL_UNINSTALLABLE_MODULE))
   # Define a copy rule to install the module.
   # acp and libraries that it uses can't use acp for
   # installation;  hence, LOCAL_ACP_UNAVAILABLE.
@@ -366,6 +366,50 @@
 endif
 
 ###########################################################
+## Compatibiliy suite files.
+###########################################################
+ifdef LOCAL_COMPATIBILITY_SUITE
+ifneq ($(words $(LOCAL_COMPATIBILITY_SUITE)),1)
+$(error $(LOCAL_PATH):$(LOCAL_MODULE) LOCAL_COMPATIBILITY_SUITE can be only one name)
+endif
+
+# The module itself.
+my_compat_dist := \
+  $(LOCAL_BUILT_MODULE):$(COMPATIBILITY_TESTCASES_OUT_$(LOCAL_COMPATIBILITY_SUITE))/$(my_installed_module_stem)
+
+# Make sure we only add the files once for multilib modules.
+ifndef $(my_prefix)$(LOCAL_MODULE_CLASS)_$(LOCAL_MODULE)_compat_files
+$(my_prefix)$(LOCAL_MODULE_CLASS)_$(LOCAL_MODULE)_compat_files := true
+
+# LOCAL_COMPATIBILITY_SUPPORT_FILES is a list of <src>[:<dest>].
+my_compat_dist += $(foreach f, $(LOCAL_COMPATIBILITY_SUPPORT_FILES),\
+  $(eval p := $(subst :,$(space),$(f)))\
+  $(eval s := $(LOCAL_PATH)/$(word 1,$(p)))\
+  $(eval d := $(COMPATIBILITY_TESTCASES_OUT_$(LOCAL_COMPATIBILITY_SUITE))/$(or $(word 2,$(p)),$(word 1,$(p))))\
+  $(s):$(d))
+
+ifneq (,$(wildcard $(LOCAL_PATH)/AndroidTest.xml))
+my_compat_dist += \
+  $(LOCAL_PATH)/AndroidTest.xml:$(COMPATIBILITY_TESTCASES_OUT_$(LOCAL_COMPATIBILITY_SUITE))/$(LOCAL_MODULE).config
+endif
+
+ifneq (,$(wildcard $(LOCAL_PATH)/DynamicConfig.xml))
+my_compat_dist += \
+  $(LOCAL_PATH)/DynamicConfig.xml:$(COMPATIBILITY_TESTCASES_OUT_$(LOCAL_COMPATIBILITY_SUITE))/$(LOCAL_MODULE).dynamic
+endif
+endif # $(my_prefix)$(LOCAL_MODULE_CLASS)_$(LOCAL_MODULE)_compat_files
+
+my_compat_files := $(call copy-many-files, $(my_compat_dist))
+
+COMPATIBILITY.$(LOCAL_COMPATIBILITY_SUITE).FILES := \
+  $(COMPATIBILITY.$(LOCAL_COMPATIBILITY_SUITE).FILES) \
+  $(my_compat_files)
+
+# Copy over the compatibility files when user runs mm/mmm.
+$(my_register_name) : $(my_compat_files)
+endif  # LOCAL_COMPATIBILITY_SUITE
+
+###########################################################
 ## Register with ALL_MODULES
 ###########################################################
 
diff --git a/core/binary.mk b/core/binary.mk
index 4cb62b3..ebb40c8 100644
--- a/core/binary.mk
+++ b/core/binary.mk
@@ -217,11 +217,13 @@
         my_clang := true
     endif
     endif
-# Add option to make clang the default for device build
-else ifeq ($(USE_CLANG_PLATFORM_BUILD),true)
+# Add option to make gcc the default for device build
+else ifeq ($(USE_CLANG_PLATFORM_BUILD),false)
     ifeq ($(my_clang),)
-        my_clang := true
+        my_clang := false
     endif
+else ifeq ($(my_clang),)
+    my_clang := true
 endif
 
 my_cpp_std_version := -std=gnu++14
@@ -522,7 +524,7 @@
 else
 ifneq (,$(LOCAL_SDK_VERSION))
 # Set target-api for LOCAL_SDK_VERSIONs other than current.
-ifneq (,$(filter-out current system_current, $(LOCAL_SDK_VERSION)))
+ifneq (,$(filter-out current system_current test_current, $(LOCAL_SDK_VERSION)))
 renderscript_target_api := $(LOCAL_SDK_VERSION)
 endif
 endif  # LOCAL_SDK_VERSION is set
diff --git a/core/clear_vars.mk b/core/clear_vars.mk
index 49e56c4..656f327 100644
--- a/core/clear_vars.mk
+++ b/core/clear_vars.mk
@@ -83,6 +83,7 @@
 LOCAL_DROIDDOC_CUSTOM_ASSET_DIR:=
 LOCAL_DROIDDOC_OPTIONS:=
 LOCAL_DROIDDOC_HTML_DIR:=
+LOCAL_DROIDDOC_STUB_OUT_DIR:=
 LOCAL_ADDITIONAL_HTML_DIR:=
 LOCAL_ASSET_DIR:=
 LOCAL_RESOURCE_DIR:=
@@ -145,6 +146,8 @@
 LOCAL_ODM_MODULE:=
 LOCAL_PRIVILEGED_MODULE:=
 LOCAL_MODULE_OWNER:=
+LOCAL_COMPATIBILITY_SUITE:=
+LOCAL_COMPATIBILITY_SUPPORT_FILES:=
 LOCAL_CTS_TEST_PACKAGE:=
 LOCAL_CTS_TEST_RUNNER:=
 LOCAL_CLANG:=
@@ -184,9 +187,11 @@
 LOCAL_DPI_FILE_STEM:=
 LOCAL_SANITIZE:=
 LOCAL_SANITIZE_RECOVER:=
+LOCAL_DATA_BINDING:=
 LOCAL_DBUS_PROXY_PREFIX:=
 LOCAL_INIT_RC:=
 LOCAL_MODULE_HOST_OS:=
+LOCAL_FINDBUGS_FLAGS:=
 LOCAL_NOTICE_FILE:=
 
 # arch specific variables
diff --git a/core/config.mk b/core/config.mk
index 37c781d..26c354d 100644
--- a/core/config.mk
+++ b/core/config.mk
@@ -35,6 +35,11 @@
 # only has an effect on python 2.6 and above.
 export PYTHONDONTWRITEBYTECODE := 1
 
+ifneq ($(GREP_OPTIONS),)
+$(warning The build system needs unmodified output of grep.)
+$(error Please unset your $$GREP_OPTIONS.)
+endif
+
 # Standard source directories.
 SRC_DOCS:= $(TOPDIR)docs
 # TODO: Enforce some kind of layering; only add include paths
@@ -57,6 +62,7 @@
 SRC_TARGET_DIR := $(TOPDIR)build/target
 SRC_API_DIR := $(TOPDIR)prebuilts/sdk/api
 SRC_SYSTEM_API_DIR := $(TOPDIR)prebuilts/sdk/system-api
+SRC_TEST_API_DIR := $(TOPDIR)prebuilts/sdk/test-api
 
 # Some specific paths to tools
 SRC_DROIDDOC_DIR := $(TOPDIR)build/tools/droiddoc
@@ -484,6 +490,7 @@
 TUNE2FS := $(HOST_OUT_EXECUTABLES)/tune2fs$(HOST_EXECUTABLE_SUFFIX)
 E2FSCK := $(HOST_OUT_EXECUTABLES)/e2fsck$(HOST_EXECUTABLE_SUFFIX)
 JARJAR := $(HOST_OUT_JAVA_LIBRARIES)/jarjar.jar
+DATA_BINDING_COMPILER := $(HOST_OUT_JAVA_LIBRARIES)/databinding-compiler.jar
 
 ifeq ($(ANDROID_COMPILE_WITH_JACK),true)
 DEFAULT_JACK_ENABLED:=full
@@ -498,7 +505,7 @@
 # Turn off jack warnings by default.
 DEFAULT_JACK_EXTRA_ARGS += --verbose error
 
-JILL := java -Xmx3500m -jar $(JILL_JAR)
+JILL := java -jar $(JILL_JAR)
 PROGUARD := external/proguard/bin/proguard.sh
 JAVATAGS := build/tools/java-event-log-tags.py
 RMTYPEDEFS := $(HOST_OUT_EXECUTABLES)/rmtypedefs
@@ -764,13 +771,15 @@
     $(patsubst $(HISTORICAL_SDK_VERSIONS_ROOT)/%/android.jar,%, \
     $(wildcard $(HISTORICAL_SDK_VERSIONS_ROOT)/*/android.jar)))
 
-# We don't have prebuilt system_current SDK yet.
-TARGET_AVAILABLE_SDK_VERSIONS := $(TARGET_AVAILABLE_SDK_VERSIONS)
+# We don't have prebuilt test_current SDK yet.
+TARGET_AVAILABLE_SDK_VERSIONS := test_current $(TARGET_AVAILABLE_SDK_VERSIONS)
 
 INTERNAL_PLATFORM_API_FILE := $(TARGET_OUT_COMMON_INTERMEDIATES)/PACKAGING/public_api.txt
 INTERNAL_PLATFORM_REMOVED_API_FILE := $(TARGET_OUT_COMMON_INTERMEDIATES)/PACKAGING/removed.txt
 INTERNAL_PLATFORM_SYSTEM_API_FILE := $(TARGET_OUT_COMMON_INTERMEDIATES)/PACKAGING/system-api.txt
 INTERNAL_PLATFORM_SYSTEM_REMOVED_API_FILE := $(TARGET_OUT_COMMON_INTERMEDIATES)/PACKAGING/system-removed.txt
+INTERNAL_PLATFORM_TEST_API_FILE := $(TARGET_OUT_COMMON_INTERMEDIATES)/PACKAGING/test-api.txt
+INTERNAL_PLATFORM_TEST_REMOVED_API_FILE := $(TARGET_OUT_COMMON_INTERMEDIATES)/PACKAGING/test-removed.txt
 
 # This is the standard way to name a directory containing prebuilt target
 # objects. E.g., prebuilt/$(TARGET_PREBUILT_TAG)/libc.so
diff --git a/core/dex_preopt.mk b/core/dex_preopt.mk
index e0dde01..de0b80a 100644
--- a/core/dex_preopt.mk
+++ b/core/dex_preopt.mk
@@ -19,6 +19,17 @@
 # The default value for LOCAL_DEX_PREOPT
 DEX_PREOPT_DEFAULT ?= true
 
+# The default values for pre-opting: always preopt PIC.
+# Conditional to building on linux, as dex2oat currently does not work on darwin.
+# Conditional to building a non-eng build, as it currently negatively affects
+# some development workflows.
+ifneq ($(TARGET_BUILD_VARIANT),eng)
+  ifeq ($(HOST_OS),linux)
+    WITH_DEXPREOPT_PIC ?= true
+    WITH_DEXPREOPT ?= true
+  endif
+endif
+
 # $(1): the .jar or .apk to remove classes.dex
 define dexpreopt-remove-classes.dex
 $(hide) zip --quiet --delete $(1) classes.dex; \
diff --git a/core/dpi_specific_apk.mk b/core/dpi_specific_apk.mk
index b2a3d64..6bae25d 100644
--- a/core/dpi_specific_apk.mk
+++ b/core/dpi_specific_apk.mk
@@ -16,7 +16,7 @@
 $(built_dpi_apk): PRIVATE_RESOURCE_DIR := $(LOCAL_RESOURCE_DIR)
 $(built_dpi_apk): PRIVATE_ASSET_DIR := $(LOCAL_ASSET_DIR)
 $(built_dpi_apk): PRIVATE_AAPT_INCLUDES := $(all_library_res_package_exports)
-ifneq (,$(filter-out current system_current, $(LOCAL_SDK_VERSION)))
+ifneq (,$(filter-out current system_current test_current, $(LOCAL_SDK_VERSION)))
 $(built_dpi_apk): PRIVATE_DEFAULT_APP_TARGET_SDK := $(LOCAL_SDK_VERSION)
 else
 $(built_dpi_apk): PRIVATE_DEFAULT_APP_TARGET_SDK := $(DEFAULT_APP_TARGET_SDK)
diff --git a/core/droiddoc.mk b/core/droiddoc.mk
index f791884..432ba11 100644
--- a/core/droiddoc.mk
+++ b/core/droiddoc.mk
@@ -68,6 +68,9 @@
   else ifeq ($(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 := $(call java-lib-files, android_test_stubs_current)
   else
     LOCAL_JAVA_LIBRARIES := sdk_v$(LOCAL_SDK_VERSION) $(LOCAL_JAVA_LIBRARIES)
     $(full_target): PRIVATE_BOOTCLASSPATH := $(call java-lib-files, sdk_v$(LOCAL_SDK_VERSION))
@@ -99,6 +102,7 @@
 
 $(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.
@@ -165,6 +169,7 @@
         $(LOCAL_ADDITIONAL_DEPENDENCIES)
 	@echo Docs droiddoc: $(PRIVATE_OUT_DIR)
 	$(hide) mkdir -p $(dir $@)
+	$(addprefix $(hide) rm -rf ,$(PRIVATE_STUB_OUT_DIR))
 	$(call prepare-doc-source-list,$(PRIVATE_SRC_LIST_FILE),$(PRIVATE_JAVA_FILES), \
 			$(PRIVATE_SOURCE_INTERMEDIATES_DIR) $(PRIVATE_ADDITIONAL_JAVA_DIR))
 	$(hide) ( \
@@ -186,6 +191,7 @@
                 -d $(PRIVATE_OUT_DIR) \
                 $(PRIVATE_CURRENT_BUILD) $(PRIVATE_CURRENT_TIME) \
                 $(PRIVATE_DROIDDOC_OPTIONS) \
+                $(addprefix -stubs ,$(PRIVATE_STUB_OUT_DIR)) \
         && touch -f $@ \
     ) || (rm -rf $(PRIVATE_OUT_DIR) $(PRIVATE_SRC_LIST_FILE); exit 45)
 
diff --git a/core/host_dalvik_java_library.mk b/core/host_dalvik_java_library.mk
index 683b8b8..550e07a 100644
--- a/core/host_dalvik_java_library.mk
+++ b/core/host_dalvik_java_library.mk
@@ -28,8 +28,7 @@
 #######################################
 
 ifneq ($(LOCAL_NO_STANDARD_LIBRARIES),true)
-  LOCAL_JAVA_LIBRARIES +=  core-oj-hostdex
-  LOCAL_JAVA_LIBRARIES +=  core-libart-hostdex
+  LOCAL_JAVA_LIBRARIES += core-oj-hostdex core-libart-hostdex
 endif
 
 full_classes_compiled_jar := $(intermediates.COMMON)/classes-full-debug.jar
diff --git a/core/host_dalvik_static_java_library.mk b/core/host_dalvik_static_java_library.mk
index 47ca002..29a1aba 100644
--- a/core/host_dalvik_static_java_library.mk
+++ b/core/host_dalvik_static_java_library.mk
@@ -24,8 +24,7 @@
 LOCAL_UNINSTALLABLE_MODULE := true
 LOCAL_IS_STATIC_JAVA_LIBRARY := true
 USE_CORE_LIB_BOOTCLASSPATH := true
-LOCAL_JAVA_LIBRARIES += core-oj-hostdex
-LOCAL_JAVA_LIBRARIES += core-libart-hostdex
+LOCAL_JAVA_LIBRARIES += core-oj-hostdex core-libart-hostdex
 
 intermediates.COMMON := $(call intermediates-dir-for,JAVA_LIBRARIES,$(LOCAL_MODULE),true,COMMON,)
 full_classes_jack := $(intermediates.COMMON)/classes.jack
diff --git a/core/java.mk b/core/java.mk
index a0ab4c5..70ff1a1 100644
--- a/core/java.mk
+++ b/core/java.mk
@@ -31,6 +31,8 @@
         LOCAL_JAVA_LIBRARIES := android_stubs_current $(LOCAL_JAVA_LIBRARIES)
       else ifeq ($(LOCAL_SDK_VERSION)$(TARGET_BUILD_APPS),system_current)
         LOCAL_JAVA_LIBRARIES := android_system_stubs_current $(LOCAL_JAVA_LIBRARIES)
+      else ifeq ($(LOCAL_SDK_VERSION)$(TARGET_BUILD_APPS),test_current)
+        LOCAL_JAVA_LIBRARIES := android_test_stubs_current $(LOCAL_JAVA_LIBRARIES)
       else
         LOCAL_JAVA_LIBRARIES := sdk_v$(LOCAL_SDK_VERSION) $(LOCAL_JAVA_LIBRARIES)
       endif
@@ -157,7 +159,7 @@
 else
   ifneq (,$(LOCAL_SDK_VERSION))
     # Set target-api for LOCAL_SDK_VERSIONs other than current.
-    ifneq (,$(filter-out current system_current, $(LOCAL_SDK_VERSION)))
+    ifneq (,$(filter-out current system_current test_current, $(LOCAL_SDK_VERSION)))
       renderscript_target_api := $(LOCAL_SDK_VERSION)
     endif
   endif  # LOCAL_SDK_VERSION is set
@@ -182,7 +184,7 @@
 renderscript_flags += $(LOCAL_RENDERSCRIPT_FLAGS)
 
 # prepend the RenderScript system include path
-ifneq ($(filter-out current system_current,$(LOCAL_SDK_VERSION))$(if $(TARGET_BUILD_APPS),$(filter current system_current,$(LOCAL_SDK_VERSION))),)
+ifneq ($(filter-out current system_current test_current,$(LOCAL_SDK_VERSION))$(if $(TARGET_BUILD_APPS),$(filter current system_current test_current,$(LOCAL_SDK_VERSION))),)
 # if a numeric LOCAL_SDK_VERSION, or current LOCAL_SDK_VERSION with TARGET_BUILD_APPS
 LOCAL_RENDERSCRIPT_INCLUDES := \
     $(HISTORICAL_SDK_VERSIONS_ROOT)/renderscript/clang-include \
@@ -290,7 +292,7 @@
 
 aidl_preprocess_import :=
 ifdef LOCAL_SDK_VERSION
-ifneq ($(filter current system_current, $(LOCAL_SDK_VERSION)$(TARGET_BUILD_APPS)),)
+ifneq ($(filter current system_current test_current, $(LOCAL_SDK_VERSION)$(TARGET_BUILD_APPS)),)
   # LOCAL_SDK_VERSION is current and no TARGET_BUILD_APPS
   aidl_preprocess_import := $(TARGET_OUT_COMMON_INTERMEDIATES)/framework.aidl
 else
@@ -475,7 +477,7 @@
 ifneq (,$(filter android-support-%,$(LOCAL_STATIC_JAVA_LIBRARIES)))
 ifdef LOCAL_SDK_VERSION
 ifdef TARGET_BUILD_APPS
-ifeq (,$(filter current system_current, $(LOCAL_SDK_VERSION)))
+ifeq (,$(filter current system_current test_current, $(LOCAL_SDK_VERSION)))
   my_support_library_sdk_raise := $(call java-lib-files, sdk_vcurrent)
 endif
 else
@@ -593,13 +595,13 @@
 endif
 
 findbugs_xml := $(intermediates.COMMON)/findbugs.xml
-$(findbugs_xml) : PRIVATE_AUXCLASSPATH := $(addprefix -auxclasspath ,$(strip \
-								$(call normalize-path-list,$(filter %.jar,\
-										$(full_java_libs)))))
-$(findbugs_xml) : $(full_classes_jar)
+$(findbugs_xml): PRIVATE_AUXCLASSPATH := $(addprefix -auxclasspath ,$(strip \
+    $(call normalize-path-list,$(filter %.jar,$(full_java_libs)))))
+$(findbugs_xml): PRIVATE_FINDBUGS_FLAGS := $(LOCAL_FINDBUGS_FLAGS)
+$(findbugs_xml) : $(full_classes_jar) $(filter %.xml, $(LOCAL_FINDBUGS_FLAGS))
 	@echo Findbugs: $@
 	$(hide) $(FINDBUGS) -textui -effort:min -xml:withMessages \
-		$(PRIVATE_AUXCLASSPATH) \
+		$(PRIVATE_AUXCLASSPATH) $(PRIVATE_FINDBUGS_FLAGS) \
 		$< \
 		> $@
 
diff --git a/core/java_common.mk b/core/java_common.mk
index aee3193..5e0dfa0 100644
--- a/core/java_common.mk
+++ b/core/java_common.mk
@@ -145,9 +145,11 @@
 my_bootclasspath := $(call java-lib-files,android_stubs_current)
 else ifeq ($(LOCAL_SDK_VERSION)$(TARGET_BUILD_APPS),system_current)
 my_bootclasspath := $(call java-lib-files,android_system_stubs_current)
+else ifeq ($(LOCAL_SDK_VERSION)$(TARGET_BUILD_APPS),test_current)
+my_bootclasspath := $(call java-lib-files,android_test_stubs_current)
 else
 my_bootclasspath := $(call java-lib-files,sdk_v$(LOCAL_SDK_VERSION))
-endif # current or system_current
+endif # current, system_current, or test_current
 endif # LOCAL_SDK_VERSION
 $(LOCAL_INTERMEDIATE_TARGETS): PRIVATE_BOOTCLASSPATH := -bootclasspath $(my_bootclasspath)
 
@@ -277,7 +279,7 @@
 ifeq ($(LOCAL_NO_STANDARD_LIBRARIES),true)
 my_bootclasspath :=
 else
-my_bootclasspath :=  $(call jack-lib-files,core-oj):$(call jack-lib-files,core-libart)
+my_bootclasspath := $(call jack-lib-files,core-oj core-libart)
 endif
 else  # LOCAL_SDK_VERSION
 ifeq ($(LOCAL_SDK_VERSION)$(TARGET_BUILD_APPS),current)
@@ -285,9 +287,11 @@
 my_bootclasspath := $(call jack-lib-files,android_stubs_current)
 else ifeq ($(LOCAL_SDK_VERSION)$(TARGET_BUILD_APPS),system_current)
 my_bootclasspath := $(call jack-lib-files,android_system_stubs_current)
+else ifeq ($(LOCAL_SDK_VERSION)$(TARGET_BUILD_APPS),test_current)
+my_bootclasspath := $(call jack-lib-files,android_test_stubs_current)
 else
 my_bootclasspath :=$(call jack-lib-files,sdk_v$(LOCAL_SDK_VERSION))
-endif # current or system_current
+endif # current, system_current, or test_current
 endif # LOCAL_SDK_VERSION
 $(LOCAL_INTERMEDIATE_TARGETS): PRIVATE_BOOTCLASSPATH_JAVA_LIBRARIES := $(my_bootclasspath)
 
@@ -304,7 +308,7 @@
 ifeq ($(LOCAL_NO_STANDARD_LIBRARIES),true)
 my_bootclasspath :=
 else
-my_bootclasspath := $(call jack-lib-files,core-oj-hostdex,$(LOCAL_IS_HOST_MODULE)):$(call jack-lib-files,core-libart-hostdex,$(LOCAL_IS_HOST_MODULE))
+my_bootclasspath := $(call jack-lib-files,core-oj-hostdex core-libart-hostdex,$(LOCAL_IS_HOST_MODULE))
 endif
 $(LOCAL_INTERMEDIATE_TARGETS): PRIVATE_BOOTCLASSPATH_JAVA_LIBRARIES := $(my_bootclasspath)
 full_shared_jack_libs := $(call jack-lib-files,$(LOCAL_JAVA_LIBRARIES),$(LOCAL_IS_HOST_MODULE))
diff --git a/core/main.mk b/core/main.mk
index d2f8414..7c979d7 100644
--- a/core/main.mk
+++ b/core/main.mk
@@ -377,18 +377,6 @@
     enable_target_debugging :=
   endif
 
-  # Turn on Dalvik preoptimization for user builds, but only if not
-  # explicitly disabled and the build is running on Linux (since host
-  # Dalvik isn't built for non-Linux hosts).
-  ifeq (,$(WITH_DEXPREOPT))
-    ifeq ($(user_variant),user)
-      ifeq ($(HOST_OS),linux)
-        # TODO: turn on WITH_DEXPREOPT for libart user builds.
-        # WITH_DEXPREOPT := true
-      endif
-    endif
-  endif
-
   # Disallow mock locations by default for user builds
   ADDITIONAL_DEFAULT_PROPERTIES += ro.allow.mock.location=0
 
@@ -424,12 +412,9 @@
           ro.setupwizard.mode=OPTIONAL
 endif
 ifndef is_sdk_build
-  # Don't verify or compile the image on eng builds to speed startup.
+  # To speedup startup of non-preopted builds, don't verify or compile the boot image.
   ADDITIONAL_BUILD_PROPERTIES += dalvik.vm.image-dex2oat-filter=verify-at-runtime
-  # Don't verify or compile apps on eng builds to speed startup.
-  ADDITIONAL_BUILD_PROPERTIES += dalvik.vm.dex2oat-filter=verify-at-runtime
 endif
-  ADDITIONAL_BUILD_PROPERTIES += dalvik.vm.usejit=true
 endif
 
 ## sdk ##
diff --git a/core/package_internal.mk b/core/package_internal.mk
index f5a00e5..ecb6913 100644
--- a/core/package_internal.mk
+++ b/core/package_internal.mk
@@ -204,6 +204,24 @@
 
 rs_compatibility_jni_libs :=
 
+ifeq ($(LOCAL_DATA_BINDING),true)
+data_binding_intermediates := $(intermediates.COMMON)/data-binding
+
+LOCAL_JAVACFLAGS += -processorpath $(DATA_BINDING_COMPILER) -s $(data_binding_intermediates)/anno-src
+LOCAL_JACK_FLAGS += --processorpath $(DATA_BINDING_COMPILER)
+
+LOCAL_STATIC_JAVA_LIBRARIES += databinding-baselibrary
+LOCAL_STATIC_JAVA_AAR_LIBRARIES += databinding-library databinding-adapters
+
+data_binding_res_in := $(LOCAL_RESOURCE_DIR)
+data_binding_res_out := $(data_binding_intermediates)/res
+
+# Replace with the processed merged res dir.
+LOCAL_RESOURCE_DIR := $(data_binding_res_out)
+
+LOCAL_AAPT_FLAGS += --auto-add-overlay --extra-packages com.android.databinding.library
+endif  # LOCAL_DATA_BINDING
+
 include $(BUILD_SYSTEM)/android_manifest.mk
 
 #################################
@@ -217,7 +235,7 @@
 
 $(LOCAL_INTERMEDIATE_TARGETS): \
     PRIVATE_ANDROID_MANIFEST := $(full_android_manifest)
-ifneq (,$(filter-out current system_current, $(LOCAL_SDK_VERSION)))
+ifneq (,$(filter-out current system_current test_current, $(LOCAL_SDK_VERSION)))
 $(LOCAL_INTERMEDIATE_TARGETS): \
     PRIVATE_DEFAULT_APP_TARGET_SDK := $(LOCAL_SDK_VERSION)
 else
@@ -225,6 +243,34 @@
     PRIVATE_DEFAULT_APP_TARGET_SDK := $(DEFAULT_APP_TARGET_SDK)
 endif
 
+ifeq ($(LOCAL_DATA_BINDING),true)
+data_binding_stamp := $(data_binding_intermediates)/data-binding.stamp
+$(data_binding_stamp): PRIVATE_INTERMEDIATES := $(data_binding_intermediates)
+$(data_binding_stamp): PRIVATE_MANIFEST := $(full_android_manifest)
+# Generate code into $(LOCAL_INTERMEDIATE_SOURCE_DIR) so that the generated .java files
+# will be automatically picked up by function compile-java.
+$(data_binding_stamp): PRIVATE_SRC_OUT := $(LOCAL_INTERMEDIATE_SOURCE_DIR)/data-binding
+$(data_binding_stamp): PRIVATE_XML_OUT := $(data_binding_intermediates)/xml
+$(data_binding_stamp): PRIVATE_RES_OUT := $(data_binding_res_out)
+$(data_binding_stamp): PRIVATE_RES_IN := $(data_binding_res_in)
+$(data_binding_stamp): PRIVATE_ANNO_SRC_DIR := $(data_binding_intermediates)/anno-src
+
+$(data_binding_stamp) : $(all_res_assets) $(full_android_manifest) \
+    $(DATA_BINDING_COMPILER)
+	@echo "Data-binding process: $@"
+	@rm -rf $(PRIVATE_INTERMEDIATES) $(PRIVATE_SRC_OUT) && \
+	  mkdir -p $(PRIVATE_INTERMEDIATES) $(PRIVATE_SRC_OUT) \
+	      $(PRIVATE_XML_OUT) $(PRIVATE_RES_OUT) $(PRIVATE_ANNO_SRC_DIR)
+	$(hide) java -classpath $(DATA_BINDING_COMPILER) android.databinding.tool.MakeCopy \
+	  $(PRIVATE_MANIFEST) $(PRIVATE_SRC_OUT) $(PRIVATE_XML_OUT) $(PRIVATE_RES_OUT) $(PRIVATE_RES_IN)
+	$(hide) touch $@
+
+# Make sure the data-binding process happens before javac and generation of R.java.
+$(R_file_stamp) $(full_classes_compiled_jar) : $(data_binding_stamp)
+# The dependency path when jack is enabled
+$(built_dex_intermediate) : $(data_binding_stamp)
+endif  # LOCAL_DATA_BINDING
+
 ifeq ($(need_compile_res),true)
 
 # Since we don't know where the real R.java file is going to end up,
@@ -315,7 +361,7 @@
 # Most packages should link against the resources defined by framework-res.
 # Even if they don't have their own resources, they may use framework
 # resources.
-ifneq ($(filter-out current system_current,$(LOCAL_SDK_RES_VERSION))$(if $(TARGET_BUILD_APPS),$(filter current system_current,$(LOCAL_SDK_RES_VERSION))),)
+ifneq ($(filter-out current system_current test_current,$(LOCAL_SDK_RES_VERSION))$(if $(TARGET_BUILD_APPS),$(filter current system_current test_current,$(LOCAL_SDK_RES_VERSION))),)
 # for released sdk versions, the platform resources were built into android.jar.
 framework_res_package_export := \
     $(HISTORICAL_SDK_VERSIONS_ROOT)/$(LOCAL_SDK_RES_VERSION)/android.jar
@@ -498,6 +544,18 @@
 
 # Make sure to install the splits when you run "make <module_name>".
 $(my_register_name): $(installed_apk_splits)
+
+ifdef LOCAL_COMPATIBILITY_SUITE
+cts_testcase_file := $(foreach s,$(my_split_suffixes),$(COMPATIBILITY_TESTCASES_OUT_$(LOCAL_COMPATIBILITY_SUITE))/$(LOCAL_MODULE)_$(s).apk)
+$(cts_testcase_file) : $(COMPATIBILITY_TESTCASES_OUT_$(LOCAL_COMPATIBILITY_SUITE))/$(LOCAL_MODULE)_%.apk : $(built_module_path)/package_%.apk | $(ACP)
+	$(copy-file-to-new-target)
+
+COMPATIBILITY.$(LOCAL_COMPATIBILITY_SUITE).FILES := \
+  $(COMPATIBILITY.$(LOCAL_COMPATIBILITY_SUITE).FILES) \
+  $(cts_testcase_file)
+
+$(my_register_name) : $(cts_testcase_file)
+endif # LOCAL_COMPATIBILITY_SUITE
 endif # LOCAL_PACKAGE_SPLITS
 
 # Save information about this package
diff --git a/core/product_config.mk b/core/product_config.mk
index 6aefa8d..fd61723 100644
--- a/core/product_config.mk
+++ b/core/product_config.mk
@@ -149,7 +149,7 @@
 unbundled_goals := $(strip $(filter APP-%,$(MAKECMDGOALS)))
 ifdef unbundled_goals
   ifneq ($(words $(unbundled_goals)),1)
-    $(error Only one APP-* goal may be specified; saw "$(unbundled_goals)"))
+    $(error Only one APP-* goal may be specified; saw "$(unbundled_goals)")
   endif
   TARGET_BUILD_APPS := $(strip $(subst -, ,$(patsubst APP-%,%,$(unbundled_goals))))
   ifneq ($(filter $(DEFAULT_GOAL),$(MAKECMDGOALS)),)
diff --git a/core/proguard.flags b/core/proguard.flags
index 0641627..6ed1f9b 100644
--- a/core/proguard.flags
+++ b/core/proguard.flags
@@ -10,9 +10,9 @@
 #-flattenpackagehierarchy
 
 # Keep classes and methods that have the guava @VisibleForTesting annotation
--keep @com.google.common.annotations.VisibleForTesting class *
+-keep @**.VisibleForTesting class *
 -keepclassmembers class * {
-@com.google.common.annotations.VisibleForTesting *;
+@**.VisibleForTesting *;
 }
 
 -include proguard_basic_keeps.flags
diff --git a/core/static_java_library.mk b/core/static_java_library.mk
index 9b7b46a..fa65d21 100644
--- a/core/static_java_library.mk
+++ b/core/static_java_library.mk
@@ -90,7 +90,7 @@
 framework_res_package_export_deps :=
 # Please refer to package.mk
 ifneq ($(LOCAL_NO_STANDARD_LIBRARIES),true)
-ifneq ($(filter-out current system_current,$(LOCAL_SDK_RES_VERSION))$(if $(TARGET_BUILD_APPS),$(filter current system_current,$(LOCAL_SDK_RES_VERSION))),)
+ifneq ($(filter-out current system_current test_current,$(LOCAL_SDK_RES_VERSION))$(if $(TARGET_BUILD_APPS),$(filter current system_current test_current,$(LOCAL_SDK_RES_VERSION))),)
 framework_res_package_export := \
     $(HISTORICAL_SDK_VERSIONS_ROOT)/$(LOCAL_SDK_RES_VERSION)/android.jar
 framework_res_package_export_deps := $(framework_res_package_export)
@@ -111,7 +111,7 @@
 $(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, $(LOCAL_SDK_VERSION)))
+ifneq (,$(filter-out current system_current test_current, $(LOCAL_SDK_VERSION)))
 $(R_file_stamp): PRIVATE_DEFAULT_APP_TARGET_SDK := $(LOCAL_SDK_VERSION)
 else
 $(R_file_stamp): PRIVATE_DEFAULT_APP_TARGET_SDK := $(DEFAULT_APP_TARGET_SDK)
diff --git a/core/tasks/apicheck.mk b/core/tasks/apicheck.mk
index 683a075..3975d20 100644
--- a/core/tasks/apicheck.mk
+++ b/core/tasks/apicheck.mk
@@ -129,4 +129,37 @@
 	@echo Copying system-removed.txt
 	$(hide) $(ACP) $(INTERNAL_PLATFORM_SYSTEM_REMOVED_API_FILE) frameworks/base/api/system-removed.txt
 
+#####################Check Test API#####################
+.PHONY: check-test-api
+checkapi : check-test-api
+
+# Check that the Test API we're building hasn't changed from the not-yet-released
+# SDK version. Note that we don't check that we haven't broken the previous
+# SDK's API because the test API is meant only for CTS which is always
+# associated with the current release.
+$(eval $(call check-api, \
+    checktestapi-current, \
+    frameworks/base/api/test-current.txt, \
+    $(INTERNAL_PLATFORM_TEST_API_FILE), \
+    frameworks/base/api/test-removed.txt, \
+    $(INTERNAL_PLATFORM_TEST_REMOVED_API_FILE), \
+    -error 2 -error 3 -error 4 -error 5 -error 6 \
+    -error 7 -error 8 -error 9 -error 10 -error 11 -error 12 -error 13 -error 14 -error 15 \
+    -error 16 -error 17 -error 18 -error 19 -error 20 -error 21 -error 23 -error 24 \
+    -error 25 -error 26 -error 27, \
+    cat $(BUILD_SYSTEM)/apicheck_msg_current.txt, \
+    check-test-api, \
+    $(call doc-timestamp-for,test-api-stubs) \
+    ))
+
+.PHONY: update-test-api
+update-api : update-test-api
+
+update-test-api: $(INTERNAL_PLATFORM_TEST_API_FILE) | $(ACP)
+	@echo Copying test-current.txt
+	$(hide) $(ACP) $(INTERNAL_PLATFORM_TEST_API_FILE) frameworks/base/api/test-current.txt
+	@echo Copying test-removed.txt
+	$(hide) $(ACP) $(INTERNAL_PLATFORM_TEST_REMOVED_API_FILE) frameworks/base/api/test-removed.txt
+
+
 endif
diff --git a/core/tasks/cts_v2.mk b/core/tasks/cts_v2.mk
new file mode 100644
index 0000000..6bb80a1
--- /dev/null
+++ b/core/tasks/cts_v2.mk
@@ -0,0 +1,24 @@
+# Copyright (C) 2015 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.
+
+test_suite_name := cts_v2
+test_suite_tradefed := cts-tradefed_v2
+test_suite_dynamic_config := cts/tools/cts-tradefed/DynamicConfig.xml
+test_suite_readme := cts/tools/cts-tradefed/README
+
+include $(BUILD_SYSTEM)/tasks/tools/compatibility.mk
+
+.PHONY: cts_v2
+cts_v2: $(compatibility_zip)
+$(call dist-for-goals, cts_v2, $(compatibility_zip))
diff --git a/core/tasks/tools/compatibility.mk b/core/tasks/tools/compatibility.mk
new file mode 100644
index 0000000..d8f900e
--- /dev/null
+++ b/core/tasks/tools/compatibility.mk
@@ -0,0 +1,52 @@
+# Copyright (C) 2015 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.
+
+# Package up a compatibility test suite in a zip file.
+#
+# Input variables:
+#   test_suite_name: the name of this test suite eg. cts
+#   test_suite_tradefed: the name of this test suite's tradefed wrapper
+#   test_suite_dynamic_config: the path to this test suite's dynamic configuration file
+#   test_suite_readme: the path to a README file for this test suite
+# Output variables:
+#   compatibility_zip: the path to the output zip file.
+
+out_dir := $(HOST_OUT)/$(test_suite_name)/android-$(test_suite_name)
+test_artifacts := $(COMPATIBILITY.$(test_suite_name).FILES)
+test_tools := $(HOST_OUT_JAVA_LIBRARIES)/hosttestlib.jar \
+  $(HOST_OUT_JAVA_LIBRARIES)/tradefed-prebuilt.jar \
+  $(HOST_OUT_JAVA_LIBRARIES)/compatibility-host-util.jar \
+  $(HOST_OUT_JAVA_LIBRARIES)/$(test_suite_tradefed).jar \
+  $(HOST_OUT_EXECUTABLES)/$(test_suite_tradefed) \
+  $(test_suite_readme)
+
+compatibility_zip := $(out_dir).zip
+$(compatibility_zip): PRIVATE_NAME := android-$(test_suite_name)
+$(compatibility_zip): PRIVATE_OUT_DIR := $(out_dir)
+$(compatibility_zip): PRIVATE_TOOLS := $(test_tools)
+$(compatibility_zip): PRIVATE_SUITE_NAME := $(test_suite_name)
+$(compatibility_zip): PRIVATE_DYNAMIC_CONFIG := $(test_suite_dynamic_config)
+$(compatibility_zip): $(test_artifacts) $(test_tools) $(test_suite_dynamic_config) | $(ADB) $(ACP)
+# Make dir structure
+	$(hide) mkdir -p $(PRIVATE_OUT_DIR)/tools $(PRIVATE_OUT_DIR)/testcases
+# Copy tools
+	$(hide) $(ACP) -fp $(PRIVATE_TOOLS) $(PRIVATE_OUT_DIR)/tools
+	$(if $(PRIVATE_DYNAMIC_CONFIG),$(hide) $(ACP) -fp $(PRIVATE_DYNAMIC_CONFIG) $(PRIVATE_OUT_DIR)/testcases/$(PRIVATE_SUITE_NAME).dynamic)
+	$(hide) cd $(dir $@) && zip -rq $(notdir $@) $(PRIVATE_NAME)
+
+# Reset all input variables
+test_suite_name :=
+test_suite_tradefed :=
+test_suite_dynamic_config :=
+test_suite_readme :=
diff --git a/core/version_defaults.mk b/core/version_defaults.mk
index 2568dc4..6ffb752 100644
--- a/core/version_defaults.mk
+++ b/core/version_defaults.mk
@@ -43,7 +43,7 @@
   # which is the version that we reveal to the end user.
   # Update this value when the platform version changes (rather
   # than overriding it somewhere else).  Can be an arbitrary string.
-  PLATFORM_VERSION := 6.0.1
+  PLATFORM_VERSION := N
 endif
 
 ifeq "" "$(PLATFORM_SDK_VERSION)"
@@ -61,7 +61,7 @@
 ifeq "" "$(PLATFORM_VERSION_CODENAME)"
   # This is the current development code-name, if the build is not a final
   # release build.  If this is a final release build, it is simply "REL".
-  PLATFORM_VERSION_CODENAME := REL
+  PLATFORM_VERSION_CODENAME := N
 
   # This is all of the development codenames that are active.  Should be either
   # the same as PLATFORM_VERSION_CODENAME or a comma-separated list of additional
@@ -82,7 +82,7 @@
     # assuming the device can only support APIs as of the previous official
     # public release.
     # This value will always be 0 for release builds.
-    PLATFORM_PREVIEW_SDK_VERSION := 0
+    PLATFORM_PREVIEW_SDK_VERSION := 1
   endif
 endif
 
diff --git a/envsetup.sh b/envsetup.sh
index f266f1a..cb3dc10 100644
--- a/envsetup.sh
+++ b/envsetup.sh
@@ -1427,6 +1427,9 @@
 
     if [ ! "$JAVA_HOME" ]; then
       if [ ! "$EXPERIMENTAL_USE_JAVA8" ]; then
+        echo JDK 8 will soon become the default. Please install it now.
+        echo Also: \"export EXPERIMENTAL_USE_JAVA8=true\"
+        echo See http://go/android-jdk8-discuss
         case `uname -s` in
             Darwin)
                 export JAVA_HOME=$(/usr/libexec/java_home -v 1.7)
diff --git a/target/board/generic/BoardConfig.mk b/target/board/generic/BoardConfig.mk
index b1cefca..aea7a37 100644
--- a/target/board/generic/BoardConfig.mk
+++ b/target/board/generic/BoardConfig.mk
@@ -77,9 +77,4 @@
 
 BOARD_SEPOLICY_DIRS += build/target/board/generic/sepolicy
 
-ifeq ($(TARGET_PRODUCT),sdk)
-  # include an expanded selection of fonts for the SDK.
-  EXTENDED_FONT_FOOTPRINT := true
-endif
-
 USE_CLANG_PLATFORM_BUILD := true
diff --git a/target/board/generic_mips/BoardConfig.mk b/target/board/generic_mips/BoardConfig.mk
index 50924f8..910107a 100644
--- a/target/board/generic_mips/BoardConfig.mk
+++ b/target/board/generic_mips/BoardConfig.mk
@@ -53,7 +53,7 @@
 USE_OPENGL_RENDERER := true
 
 TARGET_USERIMAGES_USE_EXT4 := true
-BOARD_SYSTEMIMAGE_PARTITION_SIZE := 1342177280
+BOARD_SYSTEMIMAGE_PARTITION_SIZE := 1610612736
 BOARD_USERDATAIMAGE_PARTITION_SIZE := 734003200
 BOARD_CACHEIMAGE_PARTITION_SIZE := 69206016
 BOARD_CACHEIMAGE_FILE_SYSTEM_TYPE := ext4
diff --git a/target/board/generic_mips64/BoardConfig.mk b/target/board/generic_mips64/BoardConfig.mk
index d5430cd..97fd525 100644
--- a/target/board/generic_mips64/BoardConfig.mk
+++ b/target/board/generic_mips64/BoardConfig.mk
@@ -65,7 +65,7 @@
 USE_OPENGL_RENDERER := true
 
 TARGET_USERIMAGES_USE_EXT4 := true
-BOARD_SYSTEMIMAGE_PARTITION_SIZE := 1342177280  # 1.25 GB swag, 20% more than before
+BOARD_SYSTEMIMAGE_PARTITION_SIZE := 1610612736
 BOARD_USERDATAIMAGE_PARTITION_SIZE := 1610612736  # 1.5 GB, lots of space for running tests
 BOARD_CACHEIMAGE_PARTITION_SIZE := 69206016
 BOARD_CACHEIMAGE_FILE_SYSTEM_TYPE := ext4
diff --git a/target/board/generic_x86/BoardConfig.mk b/target/board/generic_x86/BoardConfig.mk
index 44772eb..8506724 100644
--- a/target/board/generic_x86/BoardConfig.mk
+++ b/target/board/generic_x86/BoardConfig.mk
@@ -32,7 +32,7 @@
 USE_OPENGL_RENDERER := true
 
 TARGET_USERIMAGES_USE_EXT4 := true
-BOARD_SYSTEMIMAGE_PARTITION_SIZE := 1342177280  # 1.25 GB
+BOARD_SYSTEMIMAGE_PARTITION_SIZE := 1610612736
 BOARD_USERDATAIMAGE_PARTITION_SIZE := 576716800
 BOARD_CACHEIMAGE_PARTITION_SIZE := 69206016
 BOARD_CACHEIMAGE_FILE_SYSTEM_TYPE := ext4
diff --git a/target/board/generic_x86_64/BoardConfig.mk b/target/board/generic_x86_64/BoardConfig.mk
index cbfda6b..fd06e70 100755
--- a/target/board/generic_x86_64/BoardConfig.mk
+++ b/target/board/generic_x86_64/BoardConfig.mk
@@ -38,7 +38,7 @@
 USE_OPENGL_RENDERER := true
 
 TARGET_USERIMAGES_USE_EXT4 := true
-BOARD_SYSTEMIMAGE_PARTITION_SIZE := 1342177280  # 1.25 GB
+BOARD_SYSTEMIMAGE_PARTITION_SIZE := 1610612736
 BOARD_USERDATAIMAGE_PARTITION_SIZE := 576716800
 BOARD_CACHEIMAGE_PARTITION_SIZE := 69206016
 BOARD_CACHEIMAGE_FILE_SYSTEM_TYPE := ext4
diff --git a/target/product/base.mk b/target/product/base.mk
index 4c49e86..c808d0c 100644
--- a/target/product/base.mk
+++ b/target/product/base.mk
@@ -26,6 +26,7 @@
     android.test.runner \
     app_process \
     applypatch \
+    audioserver \
     blkid \
     bmgr \
     bugreport \
@@ -39,6 +40,9 @@
     hid \
     ime \
     input \
+    input.evdev.default \
+    inputflinger \
+    inputflingerhost \
     javax.obex \
     libandroid \
     libandroid_runtime \
@@ -56,6 +60,7 @@
     libeffects \
     libinput \
     libinputflinger \
+    libinputflingerhost \
     libiprouteutil \
     libjnigraphics \
     libldnhncr \
@@ -98,6 +103,7 @@
     media \
     media_cmd \
     mediaserver \
+    mediaextractor \
     monkey \
     mtpd \
     ndc \
diff --git a/target/product/core.mk b/target/product/core.mk
index 2992dbd..61b0b4a 100644
--- a/target/product/core.mk
+++ b/target/product/core.mk
@@ -43,6 +43,7 @@
     LatinIME \
     Launcher2 \
     ManagedProvisioning \
+    MtpDocumentsProvider \
     PicoTts \
     PacProcessor \
     libpac \
diff --git a/target/product/embedded.mk b/target/product/embedded.mk
index 2428585..c0811ea 100644
--- a/target/product/embedded.mk
+++ b/target/product/embedded.mk
@@ -22,6 +22,7 @@
     adbd \
     atrace \
     bootanimation \
+    cmd \
     debuggerd \
     dumpstate \
     dumpsys \
diff --git a/target/product/runtime_libart.mk b/target/product/runtime_libart.mk
index 94efe52..84fafb4 100644
--- a/target/product/runtime_libart.mk
+++ b/target/product/runtime_libart.mk
@@ -55,3 +55,4 @@
     dalvik.vm.dex2oat-Xms=64m \
     dalvik.vm.dex2oat-Xmx=512m \
     ro.dalvik.vm.native.bridge=0 \
+    dalvik.vm.usejit=true \
diff --git a/target/product/sdk_base.mk b/target/product/sdk_base.mk
index 73c2524..12a8da5 100644
--- a/target/product/sdk_base.mk
+++ b/target/product/sdk_base.mk
@@ -63,6 +63,7 @@
 	device/generic/goldfish/data/etc/apns-conf.xml:system/etc/apns-conf.xml \
 	frameworks/base/data/sounds/effects/camera_click.ogg:system/media/audio/ui/camera_click.ogg \
 	frameworks/base/data/sounds/effects/VideoRecord.ogg:system/media/audio/ui/VideoRecord.ogg \
+	frameworks/base/data/sounds/effects/VideoStop.ogg:system/media/audio/ui/VideoStop.ogg \
 	device/generic/goldfish/data/etc/handheld_core_hardware.xml:system/etc/permissions/handheld_core_hardware.xml \
 	device/generic/goldfish/camera/media_profiles.xml:system/etc/media_profiles.xml \
 	frameworks/av/media/libstagefright/data/media_codecs_google_audio.xml:system/etc/media_codecs_google_audio.xml \
diff --git a/target/product/telephony.mk b/target/product/telephony.mk
index 919d024..fdb2a71 100644
--- a/target/product/telephony.mk
+++ b/target/product/telephony.mk
@@ -21,6 +21,7 @@
     CarrierConfig \
     Dialer \
     CallLogBackup \
+    CellBroadcastReceiver \
     rild
 
 PRODUCT_COPY_FILES := \
diff --git a/tools/droiddoc/templates-ds/class.cs b/tools/droiddoc/templates-ds/class.cs
index 23e57ab..d82f1c1 100644
--- a/tools/droiddoc/templates-ds/class.cs
+++ b/tools/droiddoc/templates-ds/class.cs
@@ -184,7 +184,6 @@
     <tr class="<?cs if:count % #2 ?>alt-color<?cs /if ?> api apilevel-<?cs var:method.since ?>" >
         <td class="jd-typecol"><nobr>
             <?cs var:method.abstract ?>
-            <?cs var:method.synchronized ?>
             <?cs var:method.final ?>
             <?cs var:method.static ?>
             <?cs call:type_link(method.generic) ?>
@@ -535,7 +534,6 @@
         <?cs var:method.static ?> 
         <?cs var:method.final ?> 
         <?cs var:method.abstract ?> 
-        <?cs var:method.synchronized ?> 
         <?cs call:type_link(method.returnType) ?>
       </span>
       <span class="sympad"><?cs var:method.name ?></span>
diff --git a/tools/droiddoc/templates-ndk/class.cs b/tools/droiddoc/templates-ndk/class.cs
index 7aa99f9..e033fa2 100644
--- a/tools/droiddoc/templates-ndk/class.cs
+++ b/tools/droiddoc/templates-ndk/class.cs
@@ -188,7 +188,6 @@
     <tr class="<?cs if:count % #2 ?>alt-color<?cs /if ?> api apilevel-<?cs var:method.since ?>" >
         <td class="jd-typecol"><nobr>
             <?cs var:method.abstract ?>
-            <?cs var:method.synchronized ?>
             <?cs var:method.final ?>
             <?cs var:method.static ?>
             <?cs call:type_link(method.generic) ?>
@@ -558,7 +557,6 @@
         <?cs var:method.static ?> 
         <?cs var:method.final ?> 
         <?cs var:method.abstract ?> 
-        <?cs var:method.synchronized ?> 
         <?cs call:type_link(method.returnType) ?>
       </span>
       <span class="sympad"><?cs var:method.name ?></span>
diff --git a/tools/droiddoc/templates-sac/class.cs b/tools/droiddoc/templates-sac/class.cs
index 4003ff5..440e705 100644
--- a/tools/droiddoc/templates-sac/class.cs
+++ b/tools/droiddoc/templates-sac/class.cs
@@ -185,7 +185,6 @@
     <tr class="<?cs if:count % #2 ?>alt-color<?cs /if ?> api apilevel-<?cs var:method.since ?>" >
         <td class="jd-typecol"><nobr>
             <?cs var:method.abstract ?>
-            <?cs var:method.synchronized ?>
             <?cs var:method.final ?>
             <?cs var:method.static ?>
             <?cs call:type_link(method.generic) ?>
@@ -539,7 +538,6 @@
         <?cs var:method.static ?> 
         <?cs var:method.final ?> 
         <?cs var:method.abstract ?> 
-        <?cs var:method.synchronized ?> 
         <?cs call:type_link(method.returnType) ?>
       </span>
       <span class="sympad"><?cs var:method.name ?></span>
diff --git a/tools/droiddoc/templates-sdk-dev/class.cs b/tools/droiddoc/templates-sdk-dev/class.cs
index 693eaed..649aaff 100644
--- a/tools/droiddoc/templates-sdk-dev/class.cs
+++ b/tools/droiddoc/templates-sdk-dev/class.cs
@@ -190,7 +190,6 @@
     <tr class="<?cs if:count % #2 ?>alt-color<?cs /if ?> api apilevel-<?cs var:method.since ?>" >
         <td class="jd-typecol"><nobr>
             <?cs var:method.abstract ?>
-            <?cs var:method.synchronized ?>
             <?cs var:method.final ?>
             <?cs var:method.static ?>
             <?cs call:type_link(method.generic) ?>
@@ -560,7 +559,6 @@
         <?cs var:method.static ?> 
         <?cs var:method.final ?> 
         <?cs var:method.abstract ?> 
-        <?cs var:method.synchronized ?> 
         <?cs call:type_link(method.returnType) ?>
       </span>
       <span class="sympad"><?cs var:method.name ?></span>
diff --git a/tools/droiddoc/templates-sdk/class.cs b/tools/droiddoc/templates-sdk/class.cs
index 44eae97..93fcf88 100644
--- a/tools/droiddoc/templates-sdk/class.cs
+++ b/tools/droiddoc/templates-sdk/class.cs
@@ -188,7 +188,6 @@
     <tr class="<?cs if:count % #2 ?>alt-color<?cs /if ?> api apilevel-<?cs var:method.since ?>" >
         <td class="jd-typecol"><nobr>
             <?cs var:method.abstract ?>
-            <?cs var:method.synchronized ?>
             <?cs var:method.final ?>
             <?cs var:method.static ?>
             <?cs call:type_link(method.generic) ?>
@@ -558,7 +557,6 @@
         <?cs var:method.static ?> 
         <?cs var:method.final ?> 
         <?cs var:method.abstract ?> 
-        <?cs var:method.synchronized ?> 
         <?cs call:type_link(method.returnType) ?>
       </span>
       <span class="sympad"><?cs var:method.name ?></span>
diff --git a/tools/droiddoc/templates-sdk/components/masthead.cs b/tools/droiddoc/templates-sdk/components/masthead.cs
index 838ddbe..9db0466 100644
--- a/tools/droiddoc/templates-sdk/components/masthead.cs
+++ b/tools/droiddoc/templates-sdk/components/masthead.cs
@@ -80,7 +80,7 @@
         <?cs call:header_search_widget() ?>
         <?cs /if ?>
 
-        <?cs if:ndk ?><a class="dac-header-console-btn" href="http://developer.android.com">
+        <?cs if:ndk ?><a class="dac-header-console-btn" href="//developer.android.com">
           <span class="dac-visible-desktop-inline">Back to Android Developers</span>
         </a><?cs else ?><a class="dac-header-console-btn" href="https://play.google.com/apps/publish/">
           <span class="dac-sprite dac-google-play"></span>
@@ -281,7 +281,7 @@
     <div style="height:20px"><!-- spacer to bump header down --></div>
     <div id="butterbar-wrapper">
       <div id="butterbar">
-        <a href="http://googleblog.blogspot.com/" id="butterbar-message">
+        <a href="//googleblog.blogspot.com/" id="butterbar-message">
           The Android 5.0 SDK will be available on October 17th!
         </a>
       </div>
diff --git a/tools/droiddoc/templates-sdk/customizations.cs b/tools/droiddoc/templates-sdk/customizations.cs
index aaef8ed..d52f0e4 100644
--- a/tools/droiddoc/templates-sdk/customizations.cs
+++ b/tools/droiddoc/templates-sdk/customizations.cs
@@ -585,7 +585,7 @@
 <?cs # appears at the bottom of every page ?><?cs
 def:custom_cc_copyright() ?>
   Except as noted, this content is
-  licensed under <a href="http://creativecommons.org/licenses/by/2.5/">
+  licensed under <a href="//creativecommons.org/licenses/by/2.5/">
   Creative Commons Attribution 2.5</a>. For details and
   restrictions, see the <a href="<?cs var:toroot ?>license.html">Content
   License</a>.<?cs
@@ -594,7 +594,7 @@
 <?cs
 def:custom_copyright() ?>
   Except as noted, this content is licensed under <a
-  href="http://www.apache.org/licenses/LICENSE-2.0">Apache 2.0</a>.
+  href="//www.apache.org/licenses/LICENSE-2.0">Apache 2.0</a>.
   For details and restrictions, see the <a href="<?cs var:toroot ?>license.html">
   Content License</a>.<?cs
 /def ?>
diff --git a/tools/droiddoc/templates-sdk/designpage.cs b/tools/droiddoc/templates-sdk/designpage.cs
index b945a1c..4a523ce 100644
--- a/tools/droiddoc/templates-sdk/designpage.cs
+++ b/tools/droiddoc/templates-sdk/designpage.cs
@@ -7,7 +7,7 @@
       Android Design<?cs if:page.title ?> - <?cs var:page.title ?><?cs /if ?>
     </title>
     <link rel="shortcut icon" type="image/x-icon" href="/favicon.ico">
-    <link rel="stylesheet" href="http://fonts.googleapis.com/css?family=Roboto:regular,medium,thin,italic,mediumitalic">
+    <link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Roboto:regular,medium,thin,italic,mediumitalic">
     <link rel="stylesheet" href="<?cs var:toroot ?>assets/yui-3.3.0-reset-min.css">
     <link rel="stylesheet" href="<?cs var:toroot ?>assets/design/default.css">
     <script src="<?cs var:toroot ?>assets/jquery-1.6.2.min.js"></script>
@@ -70,16 +70,16 @@
 
         <p id="copyright">
           Except as noted, this content is licensed under
-          <a href="http://creativecommons.org/licenses/by/2.5/">
+          <a href="//creativecommons.org/licenses/by/2.5/">
           Creative Commons Attribution 2.5</a>.<br>
           For details and restrictions, see the
-          <a href="http://developer.android.com/license.html">Content License</a>.
+          <a href="//developer.android.com/license.html">Content License</a>.
         </p>
 
         <p>
-          <a href="http://www.android.com/terms.html">Site Terms of Service</a> &ndash;
-          <a href="http://www.android.com/privacy.html">Privacy Policy</a> &ndash;
-          <a href="http://www.android.com/branding.html">Brand Guidelines</a>
+          <a href="//www.android.com/terms.html">Site Terms of Service</a> &ndash;
+          <a href="//www.android.com/privacy.html">Privacy Policy</a> &ndash;
+          <a href="//www.android.com/branding.html">Brand Guidelines</a>
         </p>
 
       </div>
diff --git a/tools/droiddoc/templates-sdk/footer.cs b/tools/droiddoc/templates-sdk/footer.cs
index 1ffee63..a0900f2 100644
--- a/tools/droiddoc/templates-sdk/footer.cs
+++ b/tools/droiddoc/templates-sdk/footer.cs
@@ -7,7 +7,7 @@
       </div>
       <div class="col-1of2 dac-footer-reachout">
         <div class="dac-footer-contact">
-          <a class="dac-footer-contact-link" href="http://android-developers.blogspot.com/">Blog</a>
+          <a class="dac-footer-contact-link" href="//android-developers.blogspot.com/">Blog</a>
           <a class="dac-footer-contact-link" href="/support.html">Support</a>
         </div>
         <div class="dac-footer-social">
diff --git a/tools/droiddoc/templates-sdk/head_tag.cs b/tools/droiddoc/templates-sdk/head_tag.cs
index babb3c7..c668203 100644
--- a/tools/droiddoc/templates-sdk/head_tag.cs
+++ b/tools/droiddoc/templates-sdk/head_tag.cs
@@ -30,15 +30,15 @@
 <!-- STYLESHEETS -->
 <link rel="stylesheet"
 href="<?cs
-if:android.whichdoc != 'online' ?>http:<?cs
+if:android.whichdoc != 'online' ?>https:<?cs
 /if ?>//fonts.googleapis.com/css?family=Roboto+Condensed">
 <link rel="stylesheet" href="<?cs
-if:android.whichdoc != 'online' ?>http:<?cs
+if:android.whichdoc != 'online' ?>https:<?cs
 /if ?>//fonts.googleapis.com/css?family=Roboto:light,regular,medium,thin,italic,mediumitalic,bold"
   title="roboto">
 <?cs 
   if:ndk ?><link rel="stylesheet" href="<?cs
-  if:android.whichdoc != 'online' ?>http:<?cs
+  if:android.whichdoc != 'online' ?>https:<?cs
   /if ?>//fonts.googleapis.com/css?family=Roboto+Mono:400,500,700" title="roboto-mono" type="text/css"><?cs
 /if ?>
 <link href="<?cs var:toroot ?>assets/css/default.css?v=7" rel="stylesheet" type="text/css">
@@ -50,7 +50,7 @@
 <?cs /if ?>
 
 <!-- JAVASCRIPT -->
-<script src="<?cs if:android.whichdoc != 'online' ?>http:<?cs /if ?>//www.google.com/jsapi" type="text/javascript"></script>
+<script src="<?cs if:android.whichdoc != 'online' ?>https:<?cs /if ?>//www.google.com/jsapi" type="text/javascript"></script>
 <?cs
 if:devsite
   ?><script src="<?cs var:toroot ?>_static/js/android_3p-bundle.js" type="text/javascript"></script><?cs
diff --git a/tools/droiddoc/templates-sdk/sdkpage.cs b/tools/droiddoc/templates-sdk/sdkpage.cs
index 47c2992..401f183 100644
--- a/tools/droiddoc/templates-sdk/sdkpage.cs
+++ b/tools/droiddoc/templates-sdk/sdkpage.cs
@@ -86,7 +86,7 @@
     <td>Windows 32-bit</td>
     <td>
   <a onClick="return onDownload(this)"
-     href="http://dl.google.com/android/ndk/<?cs var:ndk.win32_download ?>"><?cs var:ndk.win32_download ?></a>
+     href="//dl.google.com/android/ndk/<?cs var:ndk.win32_download ?>"><?cs var:ndk.win32_download ?></a>
     </td>
     <td><?cs var:ndk.win32_bytes ?></td>
     <td><?cs var:ndk.win32_checksum ?></td>
@@ -94,7 +94,7 @@
  <!-- <tr>
    <td>
   <a onClick="return onDownload(this)"
-     href="http://dl.google.com/android/ndk/<?cs var:ndk.win32.legacy_download ?>"><?cs var:ndk.win32.legacy_download ?></a>
+     href="//dl.google.com/android/ndk/<?cs var:ndk.win32.legacy_download ?>"><?cs var:ndk.win32.legacy_download ?></a>
     </td>
     <td><?cs var:ndk.win32.legacy_bytes ?></td>
     <td><?cs var:ndk.win32.legacy_checksum ?></td>
@@ -103,7 +103,7 @@
     <td>Windows 64-bit</td>
     <td>
   <a onClick="return onDownload(this)"
-     href="http://dl.google.com/android/ndk/<?cs var:ndk.win64_download ?>"><?cs var:ndk.win64_download ?></a>
+     href="//dl.google.com/android/ndk/<?cs var:ndk.win64_download ?>"><?cs var:ndk.win64_download ?></a>
     </td>
     <td><?cs var:ndk.win64_bytes ?></td>
     <td><?cs var:ndk.win64_checksum ?></td>
@@ -111,7 +111,7 @@
  <!--  <tr>
     <td>
   <a onClick="return onDownload(this)"
-     href="http://dl.google.com/android/ndk/<?cs var:ndk.win64.legacy_download ?>"><?cs var:ndk.win64.legacy_download ?></a>
+     href="//dl.google.com/android/ndk/<?cs var:ndk.win64.legacy_download ?>"><?cs var:ndk.win64.legacy_download ?></a>
     </td>
     <td><?cs var:ndk.win64.legacy_bytes ?></td>
     <td><?cs var:ndk.win64.legacy_checksum ?></td>
@@ -121,7 +121,7 @@
     <td>Mac OS X 32-bit</td>
     <td>
   <a onClick="return onDownload(this)"
-     href="http://dl.google.com/android/ndk/<?cs var:ndk.mac32_download ?>"><?cs var:ndk.mac32_download ?></a>
+     href="//dl.google.com/android/ndk/<?cs var:ndk.mac32_download ?>"><?cs var:ndk.mac32_download ?></a>
     </td>
     <td><?cs var:ndk.mac32_bytes ?></td>
     <td><?cs var:ndk.mac32_checksum ?></td>
@@ -130,7 +130,7 @@
   <tr>
     <td>
   <a onClick="return onDownload(this)"
-     href="http://dl.google.com/android/ndk/<?cs var:ndk.mac32.legacy_download ?>"><?cs var:ndk.mac32.legacy_download ?></a>
+     href="//dl.google.com/android/ndk/<?cs var:ndk.mac32.legacy_download ?>"><?cs var:ndk.mac32.legacy_download ?></a>
     </td>
     <td><?cs var:ndk.mac32.legacy_bytes ?></td>
     <td><?cs var:ndk.mac32.legacy_checksum ?></td>
@@ -138,7 +138,7 @@
     <td>Mac OS X 64-bit</td>
     <td>
   <a onClick="return onDownload(this)"
-     href="http://dl.google.com/android/ndk/<?cs var:ndk.mac64_download ?>"><?cs var:ndk.mac64_download ?></a>
+     href="//dl.google.com/android/ndk/<?cs var:ndk.mac64_download ?>"><?cs var:ndk.mac64_download ?></a>
     </td>
     <td><?cs var:ndk.mac64_bytes ?></td>
     <td><?cs var:ndk.mac64_checksum ?></td>
@@ -146,7 +146,7 @@
  <!--  <tr>
     <td>
   <a onClick="return onDownload(this)"
-     href="http://dl.google.com/android/ndk/<?cs var:ndk.mac64.legacy_download ?>"><?cs var:ndk.mac64.legacy_download ?></a>
+     href="//dl.google.com/android/ndk/<?cs var:ndk.mac64.legacy_download ?>"><?cs var:ndk.mac64.legacy_download ?></a>
     </td>
     <td><?cs var:ndk.mac64.legacy_bytes ?></td>
     <td><?cs var:ndk.mac64.legacy_checksum ?></td>
@@ -155,7 +155,7 @@
     <td>Linux 32-bit (x86)</td>
     <td>
   <a onClick="return onDownload(this)"
-     href="http://dl.google.com/android/ndk/<?cs var:ndk.linux32_download ?>"><?cs var:ndk.linux32_download ?></a>
+     href="//dl.google.com/android/ndk/<?cs var:ndk.linux32_download ?>"><?cs var:ndk.linux32_download ?></a>
     </td>
     <td><?cs var:ndk.linux32_bytes ?></td>
     <td><?cs var:ndk.linux32_checksum ?></td>
@@ -163,7 +163,7 @@
  <!--  <tr>
     <td>
   <a onClick="return onDownload(this)"
-     href="http://dl.google.com/android/ndk/<?cs var:ndk.linux32.legacy_download ?>"><?cs var:ndk.linux32.legacy_download ?></a>
+     href="//dl.google.com/android/ndk/<?cs var:ndk.linux32.legacy_download ?>"><?cs var:ndk.linux32.legacy_download ?></a>
     </td>
     <td><?cs var:ndk.linux32.legacy_bytes ?></td>
     <td><?cs var:ndk.linux32.legacy_checksum ?></td>
@@ -172,7 +172,7 @@
     <td>Linux 64-bit (x86)</td>
     <td>
   <a onClick="return onDownload(this)"
-     href="http://dl.google.com/android/ndk/<?cs var:ndk.linux64_download ?>"><?cs var:ndk.linux64_download ?></a>
+     href="//dl.google.com/android/ndk/<?cs var:ndk.linux64_download ?>"><?cs var:ndk.linux64_download ?></a>
     </td>
     <td><?cs var:ndk.linux64_bytes ?></td>
     <td><?cs var:ndk.linux64_checksum ?></td>
@@ -180,7 +180,7 @@
   <!--  <tr>
     <td>
   <a onClick="return onDownload(this)"
-     href="http://dl.google.com/android/ndk/<?cs var:ndk.linux64.legacy_download ?>"><?cs var:ndk.linux64.legacy_download ?></a>
+     href="//dl.google.com/android/ndk/<?cs var:ndk.linux64.legacy_download ?>"><?cs var:ndk.linux64.legacy_download ?></a>
     </td>
     <td><?cs var:ndk.linux64.legacy_bytes ?></td>
     <td><?cs var:ndk.linux64.legacy_checksum ?></td>
@@ -286,7 +286,7 @@
   <tr>
     <td rowspan="2">Windows</td>
     <td>
-  <a onclick="return onDownload(this)" id="win-tools" href="http://dl.google.com/android/<?cs
+  <a onclick="return onDownload(this)" id="win-tools" href="//dl.google.com/android/<?cs
 var:sdk.win_installer
 ?>"><?cs var:sdk.win_installer ?></a> (Recommended)
     </td>
@@ -296,7 +296,7 @@
   <tr>
     <!-- blank TD from Windows rowspan -->
     <td>
-  <a onclick="return onDownload(this)" href="http://dl.google.com/android/<?cs var:sdk.win_download
+  <a onclick="return onDownload(this)" href="//dl.google.com/android/<?cs var:sdk.win_download
 ?>"><?cs var:sdk.win_download ?></a>
     </td>
     <td><?cs var:sdk.win_bytes ?> bytes</td>
@@ -305,7 +305,7 @@
   <tr>
     <td><nobr>Mac OS X</nobr></td>
     <td>
-  <a onclick="return onDownload(this)" id="mac-tools" href="http://dl.google.com/android/<?cs
+  <a onclick="return onDownload(this)" id="mac-tools" href="//dl.google.com/android/<?cs
 var:sdk.mac_download
 ?>"><?cs var:sdk.mac_download ?></a>
     </td>
@@ -315,7 +315,7 @@
   <tr>
     <td>Linux</td>
     <td>
-  <a onclick="return onDownload(this)" id="linux-tools" href="http://dl.google.com/android/<?cs
+  <a onclick="return onDownload(this)" id="linux-tools" href="//dl.google.com/android/<?cs
 var:sdk.linux_download
 ?>"><?cs var:sdk.linux_download ?></a>
     </td>
diff --git a/tools/releasetools/common.py b/tools/releasetools/common.py
index aaf51e9..95aeb62 100644
--- a/tools/releasetools/common.py
+++ b/tools/releasetools/common.py
@@ -1241,9 +1241,6 @@
     self.partition = partition
     self.check_first_block = check_first_block
 
-    # Due to http://b/20939131, check_first_block is disabled temporarily.
-    assert not self.check_first_block
-
     if version is None:
       version = 1
       if OPTIONS.info_dict:
@@ -1307,14 +1304,8 @@
         script.AppendExtra(('if (range_sha1("%s", "%s") == "%s" || '
                             'block_image_verify("%s", '
                             'package_extract_file("%s.transfer.list"), '
-                            '"%s.new.dat", "%s.patch.dat") || '
-                            '(block_image_recover("%s", "%s") && '
-                            'block_image_verify("%s", '
-                            'package_extract_file("%s.transfer.list"), '
-                            '"%s.new.dat", "%s.patch.dat"))) then') % (
+                            '"%s.new.dat", "%s.patch.dat")) then') % (
                             self.device, ranges_str, self.src.TotalSha1(),
-                            self.device, partition, partition, partition,
-                            self.device, ranges_str,
                             self.device, partition, partition, partition))
       elif self.version == 3:
         script.AppendExtra(('if (range_sha1("%s", "%s") == "%s" || '
@@ -1329,22 +1320,36 @@
       script.Print('Verified %s image...' % (partition,))
       script.AppendExtra('else')
 
-      # When generating incrementals for the system and vendor partitions,
-      # explicitly check the first block (which contains the superblock) of
-      # the partition to see if it's what we expect. If this check fails,
-      # give an explicit log message about the partition having been
-      # remounted R/W (the most likely explanation) and the need to flash to
-      # get OTAs working again.
-      if self.check_first_block:
-        self._CheckFirstBlock(script)
+      if self.version >= 4:
+
+        # Bug: 21124327
+        # When generating incrementals for the system and vendor partitions in
+        # version 4 or newer, explicitly check the first block (which contains
+        # the superblock) of the partition to see if it's what we expect. If
+        # this check fails, give an explicit log message about the partition
+        # having been remounted R/W (the most likely explanation).
+        if self.check_first_block:
+          script.AppendExtra('check_first_block("%s");' % (self.device,))
+
+        # If version >= 4, try block recovery before abort update
+        script.AppendExtra((
+            'ifelse (block_image_recover("{device}", "{ranges}") && '
+            'block_image_verify("{device}", '
+            'package_extract_file("{partition}.transfer.list"), '
+            '"{partition}.new.dat", "{partition}.patch.dat"), '
+            'ui_print("{partition} recovered successfully."), '
+            'abort("{partition} partition fails to recover"));\n'
+            'endif;').format(device=self.device, ranges=ranges_str,
+                             partition=partition))
 
       # Abort the OTA update. Note that the incremental OTA cannot be applied
       # even if it may match the checksum of the target partition.
       # a) If version < 3, operations like move and erase will make changes
       #    unconditionally and damage the partition.
       # b) If version >= 3, it won't even reach here.
-      script.AppendExtra(('abort("%s partition has unexpected contents");\n'
-                          'endif;') % (partition,))
+      else:
+        script.AppendExtra(('abort("%s partition has unexpected contents");\n'
+                            'endif;') % (partition,))
 
   def _WritePostInstallVerifyScript(self, script):
     partition = self.partition
@@ -1413,22 +1418,9 @@
 
     return ctx.hexdigest()
 
-  # TODO(tbao): Due to http://b/20939131, block 0 may be changed without
-  # remounting R/W. Will change the checking to a finer-grained way to
-  # mask off those bits.
-  def _CheckFirstBlock(self, script):
-    r = rangelib.RangeSet((0, 1))
-    srchash = self._HashBlocks(self.src, r)
-
-    script.AppendExtra(('(range_sha1("%s", "%s") == "%s") || '
-                        'abort("%s has been remounted R/W; '
-                        'reflash device to reenable OTA updates");')
-                       % (self.device, r.to_string_raw(), srchash,
-                          self.device))
 
 DataImage = blockimgdiff.DataImage
 
-
 # map recovery.fstab's fs_types to mount/format "partition types"
 PARTITION_TYPES = {
     "yaffs2": "MTD",
diff --git a/tools/releasetools/ota_from_target_files.py b/tools/releasetools/ota_from_target_files.py
index a76eaa9..d0636b6 100755
--- a/tools/releasetools/ota_from_target_files.py
+++ b/tools/releasetools/ota_from_target_files.py
@@ -811,7 +811,12 @@
         int(i) for i in
         OPTIONS.info_dict.get("blockimgdiff_versions", "1").split(","))
 
+  # Check first block of system partition for remount R/W only if
+  # disk type is ext4
+  system_partition = OPTIONS.source_info_dict["fstab"]["/system"]
+  check_first_block = system_partition.fs_type=="ext4"
   system_diff = common.BlockDifference("system", system_tgt, system_src,
+                                       check_first_block,
                                        version=blockimgdiff_version)
 
   if HasVendorPartition(target_zip):
@@ -821,7 +826,13 @@
                           OPTIONS.source_info_dict)
     vendor_tgt = GetImage("vendor", OPTIONS.target_tmp,
                           OPTIONS.target_info_dict)
+
+    # Check first block of vendor partition for remount R/W only if
+    # disk type is ext4
+    vendor_partition = OPTIONS.source_info_dict["fstab"]["/vendor"]
+    check_first_block = vendor_partition.fs_type=="ext4"
     vendor_diff = common.BlockDifference("vendor", vendor_tgt, vendor_src,
+                                         check_first_block,
                                          version=blockimgdiff_version)
   else:
     vendor_diff = None