Switch frameworks/base/core/jni from gcc to clang.

Bug: http://b/22414716

Change-Id: If77628daf4e621008cda96645a9fffbf0fba4992
diff --git a/core/jni/Android.mk b/core/jni/Android.mk
index 37204988..9e58944 100644
--- a/core/jni/Android.mk
+++ b/core/jni/Android.mk
@@ -279,10 +279,6 @@
 #                        is not being compiled with that level. Remove once this has changed.
 LOCAL_CLANG_CFLAGS += -Wno-c++11-extensions
 
-# b/22414716: thread_local (android/graphics/Paint.cpp) and Clang don't like each other at the
-#             moment.
-LOCAL_CLANG := false
-
 include $(BUILD_SHARED_LIBRARY)
 
 include $(call all-makefiles-under,$(LOCAL_PATH))