libmediaplayerservice: fix warnings, make warnings errors, use clang

Change-Id: I1b2f6b65c5abbc366068a60b8909104f31b94228
diff --git a/media/libmediaplayerservice/tests/Android.mk b/media/libmediaplayerservice/tests/Android.mk
index 7bc78ff..8cbf782 100644
--- a/media/libmediaplayerservice/tests/Android.mk
+++ b/media/libmediaplayerservice/tests/Android.mk
@@ -18,6 +18,9 @@
 	frameworks/av/include \
 	frameworks/av/media/libmediaplayerservice \
 
+LOCAL_CFLAGS += -Werror -Wall
+LOCAL_CLANG := true
+
 LOCAL_32_BIT_ONLY := true
 
 include $(BUILD_NATIVE_TEST)