Building Mir outputs lots of warnings about Android logging functions in 3rd_party/

Building Mir outputs lots of warnings about Android logging functions. It would be nice if we could filter these out so we didn't become blind to all warnings in 3rd_party...

[ 5%] In file included from /home/dan/bzr/mir/dev/3rd_party/android-input/android/frameworks/base/services/input/InputDispatcher.cpp:50:0:
/home/dan/bzr/mir/dev/3rd_party/android-input/android/frameworks/base/services/input/InputDispatcher.cpp: In function ‘bool android::validateMotionEvent(int32_t, size_t, const android::PointerProperties*)’:
/home/dan/bzr/mir/dev/3rd_party/android-deps/cutils/log.h:421:47: warning: format ‘%d’ expects argument of type ‘int’, but argument 4 has type ‘size_t {aka long unsigned int}’ [-Wformat=]
     __android_log_print(prio, tag, __VA_ARGS__)
                                               ^
/home/dan/bzr/mir/dev/3rd_party/android-deps/cutils/log.h:357:5: note: in expansion of macro ‘android_printLog’
     android_printLog(priority, tag, __VA_ARGS__)
     ^
/home/dan/bzr/mir/dev/3rd_party/android-deps/cutils/log.h:349:5: note: in expansion of macro ‘LOG_PRI’
     LOG_PRI(ANDROID_##priority, tag, __VA_ARGS__)
     ^
/home/dan/bzr/mir/dev/3rd_party/android-deps/cutils/log.h:143:27: note: in expansion of macro ‘ALOG’
 #define ALOGE(...) ((void)ALOG(LOG_ERROR, LOG_TAG, __VA_ARGS__))
                           ^
/home/dan/bzr/mir/dev/3rd_party/android-input/android/frameworks/base/services/input/InputDispatcher.cpp:151:9: note: in expansion of macro ‘ALOGE’
         ALOGE("Motion event has invalid pointer count %d; value must be between 1 and %d.",
         ^