change AudioTrack mode to MUSIC & add details to report

- mobile phones activates the Receiver speaker for VOICE_CALL mode
- this can pull additional processing, but the test should test the
  loud speaker.
- added details to report to collect save results
- changed buffering of FileUtil to accomodate longer message

Change-Id: Ifdbb9fbfcf80c630c8952599b7e65eb909735a94
12 files changed