diff --git a/core/Makefile b/core/Makefile
index e8e592a..7205a8c 100644
--- a/core/Makefile
+++ b/core/Makefile
@@ -421,7 +421,6 @@
 	        BUILD_HOSTNAME="$(BUILD_HOSTNAME)" \
 	        BUILD_NUMBER="$(BUILD_NUMBER_FROM_FILE)" \
 	        BOARD_BUILD_SYSTEM_ROOT_IMAGE="$(BOARD_BUILD_SYSTEM_ROOT_IMAGE)" \
-	        AB_OTA_UPDATER="$(AB_OTA_UPDATER)" \
 	        PLATFORM_VERSION="$(PLATFORM_VERSION)" \
 	        PLATFORM_SECURITY_PATCH="$(PLATFORM_SECURITY_PATCH)" \
 	        PLATFORM_BASE_OS="$(PLATFORM_BASE_OS)" \
@@ -498,6 +497,9 @@
 ifdef TARGET_SCREEN_DENSITY
 	$(hide) echo ro.sf.lcd_density="$(TARGET_SCREEN_DENSITY)">>$@
 endif
+ifeq ($(AB_OTA_UPDATER),true)
+	$(hide) echo ro.build.ab_update=true >> $@
+endif
 	$(hide) $(call generate-common-build-props,vendor,$@)
 	$(hide) echo "#" >> $@; \
 	        echo "# BOOTIMAGE_BUILD_PROPERTIES" >> $@; \
@@ -1980,14 +1982,19 @@
 
 $(INSTALLED_DEBUG_RAMDISK_TARGET): DEBUG_RAMDISK_SYNC_DIR := $(my_debug_ramdisk_sync_dir)
 $(INSTALLED_DEBUG_RAMDISK_TARGET): DEBUG_RAMDISK_ROOT_DIR := $(my_debug_ramdisk_root_dir)
-# We should have just depended on ramdisk.img or ramdisk-recovery.img.
-# But ramdisk-recovery.img is not a make target, so let's depend on the boot.img directly.
+
+ifeq ($(BOARD_USES_RECOVERY_AS_BOOT),true)
+# ramdisk-recovery.img isn't a make target, need to depend on boot.img if it's for recovery.
 $(INSTALLED_DEBUG_RAMDISK_TARGET): $(INSTALLED_BOOTIMAGE_TARGET)
+else
+# Depends on ramdisk.img, note that some target has ramdisk.img but no boot.img, e.g., emulator.
+$(INSTALLED_DEBUG_RAMDISK_TARGET): $(INSTALLED_RAMDISK_TARGET)
+endif # BOARD_USES_RECOVERY_AS_BOOT
 $(INSTALLED_DEBUG_RAMDISK_TARGET): $(MKBOOTFS) $(INTERNAL_DEBUG_RAMDISK_FILES) | $(MINIGZIP)
 	$(call pretty,"Target debug ram disk: $@")
 	mkdir -p $(TARGET_DEBUG_RAMDISK_OUT)
 	touch $(TARGET_DEBUG_RAMDISK_OUT)/force_debuggable
-	rsync -a $(DEBUG_RAMDISK_SYNC_DIR)/* $(DEBUG_RAMDISK_ROOT_DIR)
+	rsync -a $(DEBUG_RAMDISK_SYNC_DIR)/ $(DEBUG_RAMDISK_ROOT_DIR)
 	$(MKBOOTFS) -d $(TARGET_OUT) $(DEBUG_RAMDISK_ROOT_DIR) | $(MINIGZIP) > $@
 
 .PHONY: ramdisk_debug-nodeps
@@ -1997,7 +2004,7 @@
 	echo "make $@: ignoring dependencies"
 	mkdir -p $(TARGET_DEBUG_RAMDISK_OUT)
 	touch $(TARGET_DEBUG_RAMDISK_OUT)/force_debuggable
-	rsync -a $(DEBUG_RAMDISK_SYNC_DIR)/* $(DEBUG_RAMDISK_ROOT_DIR)
+	rsync -a $(DEBUG_RAMDISK_SYNC_DIR)/ $(DEBUG_RAMDISK_ROOT_DIR)
 	$(MKBOOTFS) -d $(TARGET_OUT) $(DEBUG_RAMDISK_ROOT_DIR) | $(MINIGZIP) > $(INSTALLED_DEBUG_RAMDISK_TARGET)
 
 my_debug_ramdisk_sync_dir :=
diff --git a/core/definitions.mk b/core/definitions.mk
index 1f5c5ce..aa2a2a9 100644
--- a/core/definitions.mk
+++ b/core/definitions.mk
@@ -1997,26 +1997,6 @@
         @$(call emit-line,$(wordlist 13001,13500,$(1)),$(2))
         @$(if $(wordlist 13501,13502,$(1)),$(error Too many words ($(words $(1)))))
 endef
-
-# For a list of jar files, unzip them to a specified directory,
-# but make sure that no META-INF files come along for the ride,
-# unless PRIVATE_DONT_DELETE_JAR_META_INF is set.
-#
-# $(1): files to unzip
-# $(2): destination directory
-define unzip-jar-files
-  $(hide) for f in $(1); \
-  do \
-    if [ ! -f $$f ]; then \
-      echo Missing file $$f; \
-      exit 1; \
-    fi; \
-    unzip -qo $$f -d $(2); \
-    rm -f $(2)/module-info.class; \
-  done
-  $(if $(PRIVATE_DONT_DELETE_JAR_META_INF),,$(hide) rm -rf $(2)/META-INF)
-endef
-
 # Return jar arguments to compress files in a given directory
 # $(1): directory
 #
diff --git a/core/host_dalvik_java_library.mk b/core/host_dalvik_java_library.mk
index 2a251e8..1545f63 100644
--- a/core/host_dalvik_java_library.mk
+++ b/core/host_dalvik_java_library.mk
@@ -104,7 +104,6 @@
 ifneq ($(TURBINE_ENABLED),false)
 
 $(full_classes_turbine_jar): PRIVATE_JAVACFLAGS := $(LOCAL_JAVACFLAGS) $(annotation_processor_flags)
-$(full_classes_turbine_jar): PRIVATE_DONT_DELETE_JAR_META_INF := $(LOCAL_DONT_DELETE_JAR_META_INF)
 $(full_classes_turbine_jar): PRIVATE_SRCJARS := $(LOCAL_SRCJARS)
 $(full_classes_turbine_jar): \
     $(java_source_list_file) \
diff --git a/core/host_java_library.mk b/core/host_java_library.mk
index c8d2ee7..f7bf337 100644
--- a/core/host_java_library.mk
+++ b/core/host_java_library.mk
@@ -95,13 +95,15 @@
 javac-check-$(LOCAL_MODULE) : $(full_classes_compiled_jar)
 .PHONY: javac-check-$(LOCAL_MODULE)
 
+$(full_classes_combined_jar): PRIVATE_DONT_DELETE_JAR_META_INF := $(LOCAL_DONT_DELETE_JAR_META_INF)
 $(full_classes_combined_jar): $(full_classes_compiled_jar) \
                               $(jar_manifest_file) \
                               $(full_static_java_libs) | $(MERGE_ZIPS)
 	$(if $(PRIVATE_JAR_MANIFEST), $(hide) sed -e "s/%BUILD_NUMBER%/$(BUILD_NUMBER_FROM_FILE)/" \
             $(PRIVATE_JAR_MANIFEST) > $(dir $@)/manifest.mf)
 	$(MERGE_ZIPS) -j --ignore-duplicates $(if $(PRIVATE_JAR_MANIFEST),-m $(dir $@)/manifest.mf) \
-            -stripDir META-INF -zipToNotStrip $< $@ $< $(call reverse-list,$(PRIVATE_STATIC_JAVA_LIBRARIES))
+            $(if $(PRIVATE_DONT_DELETE_JAR_META_INF),,-stripDir META-INF -zipToNotStrip $<) \
+            $@ $< $(call reverse-list,$(PRIVATE_STATIC_JAVA_LIBRARIES))
 
 # Run jarjar if necessary, otherwise just copy the file.
 ifneq ($(strip $(LOCAL_JARJAR_RULES)),)
diff --git a/core/java.mk b/core/java.mk
index 40fa594..afc77d6 100644
--- a/core/java.mk
+++ b/core/java.mk
@@ -244,7 +244,6 @@
 
 $(full_classes_turbine_jar): PRIVATE_JAVACFLAGS := $(LOCAL_JAVACFLAGS) $(annotation_processor_flags)
 $(full_classes_turbine_jar): PRIVATE_SRCJARS := $(LOCAL_SRCJARS)
-$(full_classes_turbine_jar): PRIVATE_DONT_DELETE_JAR_META_INF := $(LOCAL_DONT_DELETE_JAR_META_INF)
 $(full_classes_turbine_jar): \
     $(java_source_list_file) \
     $(java_sources_deps) \
@@ -278,7 +277,6 @@
 $(full_classes_compiled_jar): PRIVATE_JAR_EXCLUDE_FILES := $(LOCAL_JAR_EXCLUDE_FILES)
 $(full_classes_compiled_jar): PRIVATE_JAR_PACKAGES := $(LOCAL_JAR_PACKAGES)
 $(full_classes_compiled_jar): PRIVATE_JAR_EXCLUDE_PACKAGES := $(LOCAL_JAR_EXCLUDE_PACKAGES)
-$(full_classes_compiled_jar): PRIVATE_DONT_DELETE_JAR_META_INF := $(LOCAL_DONT_DELETE_JAR_META_INF)
 $(full_classes_compiled_jar): PRIVATE_JAVA_SOURCE_LIST := $(java_source_list_file)
 $(full_classes_compiled_jar): PRIVATE_ALL_JAVA_HEADER_LIBRARIES := $(full_java_header_libs)
 $(full_classes_compiled_jar): PRIVATE_SRCJARS := $(LOCAL_SRCJARS)
diff --git a/tools/buildinfo.sh b/tools/buildinfo.sh
index 24ac663..09d8f70 100755
--- a/tools/buildinfo.sh
+++ b/tools/buildinfo.sh
@@ -25,9 +25,6 @@
 if [ -n "$BOARD_BUILD_SYSTEM_ROOT_IMAGE" ] ; then
   echo "ro.build.system_root_image=$BOARD_BUILD_SYSTEM_ROOT_IMAGE"
 fi
-if [ -n "$AB_OTA_UPDATER" ] ; then
-  echo "ro.build.ab_update=$AB_OTA_UPDATER"
-fi
 
 # These values are deprecated, use "ro.product.cpu.abilist"
 # instead (see below).