libsync: Turn on -Werror

Change-Id: Ie34f935694034a069e844be64d6011eb9e3f9869
diff --git a/libsync/Android.mk b/libsync/Android.mk
index 626b762..fd1c88c 100644
--- a/libsync/Android.mk
+++ b/libsync/Android.mk
@@ -7,6 +7,7 @@
 LOCAL_SHARED_LIBRARIES := liblog
 LOCAL_C_INCLUDES := $(LOCAL_PATH)/include
 LOCAL_EXPORT_C_INCLUDE_DIRS := $(LOCAL_PATH)/include
+LOCAL_CFLAGS := -Werror
 include $(BUILD_SHARED_LIBRARY)
 
 include $(CLEAR_VARS)
@@ -15,4 +16,5 @@
 LOCAL_MODULE_TAGS := optional tests
 LOCAL_SHARED_LIBRARIES := liblog
 LOCAL_C_INCLUDES := $(LOCAL_PATH)/include
+LOCAL_CFLAGS := -Werror
 include $(BUILD_EXECUTABLE)