henrika c103653113 Avoids WebRtcAudioTrack null pointer access at stop.
Example of new stop sequence:

PID   TID
5155  5189 I WebRtcAudioTrack: stopPlayout
5155  5189 I WebRtcAudioTrack: underrun count: 0
5155  5189 I WebRtcAudioTrack: stopThread
5155  5189 I WebRtcAudioTrack: Stopping the AudioTrackThread...

5155  5236 I WebRtcAudioTrack: Stopping and flushing the audio track...
5155  5236 I WebRtcAudioTrack: The audio track has now been stopped.

5155  5189 I WebRtcAudioTrack: AudioTrackThread has now been stopped.
5155  5189 I WebRtcAudioTrack: releaseAudioResources

BUG=b/64692432

Review-Url: https://codereview.webrtc.org/3001703002
Cr-Commit-Position: refs/heads/master@{#19370}
2017-08-16 13:14:08 +00:00
..
2017-08-09 13:42:32 +00:00
2015-11-16 19:02:02 +00:00
2017-06-30 10:04:59 +00:00

Name: WebRTC
URL: http://www.webrtc.org
Version: 90
License: BSD
License File: LICENSE

Description:
WebRTC provides real time voice and video processing
functionality to enable the implementation of 
PeerConnection/MediaStream.

Third party code used in this project is described 
in the file LICENSE_THIRD_PARTY.