Use -Werror in packages/apps/Messaging/jni

Bug: 66996870
Test: build with WITH_TIDY=1
Change-Id: I3d7f5b98523c9fee08f2d1c29178ae050923617c
diff --git a/jni/Android.mk b/jni/Android.mk
index dbc0674..cb9a69c 100644
--- a/jni/Android.mk
+++ b/jni/Android.mk
@@ -27,7 +27,7 @@
 LOCAL_MODULE    := libgiftranscode
 LOCAL_SRC_FILES := GifTranscoder.cpp
 
-LOCAL_CFLAGS += -Wall -Wno-unused-parameter -Wno-switch
+LOCAL_CFLAGS += -Wall -Werror -Wno-unused-parameter -Wno-switch
 
 LOCAL_SDK_VERSION := 19
 LOCAL_NDK_STL_VARIANT := c++_static # LLVM libc++