diff --git a/core/binary.mk b/core/binary.mk
index 2f306b2..c468079 100644
--- a/core/binary.mk
+++ b/core/binary.mk
@@ -187,7 +187,7 @@
   endif
   LOCAL_NDK_STL_VARIANT := $(strip $(LOCAL_NDK_STL_VARIANT))
   ifeq (,$(LOCAL_NDK_STL_VARIANT))
-    LOCAL_NDK_STL_VARIANT := system
+    LOCAL_NDK_STL_VARIANT := c++_shared
   endif
   ifneq (1,$(words $(filter none system stlport_static stlport_shared c++_static c++_shared gnustl_static, $(LOCAL_NDK_STL_VARIANT))))
     $(error $(LOCAL_PATH): Unknown LOCAL_NDK_STL_VARIANT $(LOCAL_NDK_STL_VARIANT))
diff --git a/core/soong_app_prebuilt.mk b/core/soong_app_prebuilt.mk
index 0b8fa4d..e94c019 100644
--- a/core/soong_app_prebuilt.mk
+++ b/core/soong_app_prebuilt.mk
@@ -43,6 +43,12 @@
 	$(call dexpreopt-one-file,$<,$@)
 endif
 
+PACKAGES := $(PACKAGES) $(LOCAL_MODULE)
+ifdef LOCAL_CERTIFICATE
+  PACKAGES.$(LOCAL_MODULE).PRIVATE_KEY := $(LOCAL_CERTIFICATE)
+  PACKAGES.$(LOCAL_MODULE).CERTIFICATE := $(patsubst %.x509.pem,%.pk8,$(LOCAL_CERTIFICATE))
+endif
+
 ifndef LOCAL_IS_HOST_MODULE
 ifeq ($(LOCAL_SDK_VERSION),system_current)
 my_link_type := java:system
diff --git a/tools/releasetools/ota_from_target_files.py b/tools/releasetools/ota_from_target_files.py
index 60aa84e..d2041e8 100755
--- a/tools/releasetools/ota_from_target_files.py
+++ b/tools/releasetools/ota_from_target_files.py
@@ -58,7 +58,7 @@
       very rarely used, since it's expected to have a dedicated OEM partition
       for OEM-specific properties. Only meaningful when -o is specified.
 
-  -w  (--wipe_user_data)
+  --wipe_user_data
       Generate an OTA package that will wipe the user data partition
       when installed.
 
@@ -1295,7 +1295,7 @@
       OPTIONS.full_radio = True
     elif o == "--full_bootloader":
       OPTIONS.full_bootloader = True
-    elif o in ("-w", "--wipe_user_data"):
+    elif o == "--wipe_user_data":
       OPTIONS.wipe_user_data = True
     elif o == "--downgrade":
       OPTIONS.downgrade = True
@@ -1347,7 +1347,7 @@
     return True
 
   args = common.ParseOptions(argv, __doc__,
-                             extra_opts="b:k:i:d:we:t:2o:",
+                             extra_opts="b:k:i:d:e:t:2o:",
                              extra_long_opts=[
                                  "package_key=",
                                  "incremental_from=",