Cleanup CreateAudioPlayer and CreateMediaPlayer

Fix minor bug in MediaPlayer, it was missing an assignment if invalid locator:
    mp->mAndroidObjType = INVALID_TYPE;

Cleanup:
 - add placeholders for android::AudioSystem::acquireAudioSessionId and
   releaseAudioSessionId
 - remove duplicate initialization of some fields.
 - android_audioPlayer_create can never fail, so make it return void
 - add comments
 - remove unused method audioPlayer_setInvalid
 - simplify android_audioPlayer_create

Change-Id: I237b796f6b828cf53bf2c628e52a05a4bdf86c06
4 files changed
tree: 6ac48fcdcf3023f5b672b002672e672af843cff1
  1. doc/
  2. include/
  3. src/
  4. tests/
  5. tools/