am 7e397842: Reduce memory usage by the MP4 file writer - Don\'t store...

am 7e397842: Reduce memory usage by the MP4 file writer - Don\'t store timestamp for each output sample - Don\'t store timestamp for statistical data collection if the collection of statistical data is not requested

Merge commit '7e397842' into gingerbread-plus-aosp

* commit '7e397842':
  Reduce memory usage by the MP4 file writer