Merge changes Iefbea3b1,Ieb924b6d am: bb51fbc4d4 am: 9d4203aae1
am: 91a7685e65

* commit '91a7685e653234ae99547ca9cfeac3ea7de17307':
  liblog: add android_log_timestamp() private function
  liblog: logcat: add epoch and monotonic format modifiers