Avoids WebRtcAudioTrack null pointer access at stop

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}
Committed: https://chromium.googlesource.com/external/webrtc/+/c103653113ebe6dbe11e7455c2c4f500c1fbbf8b

[henrika_webrtc, 2017-08-15 13:34:45]

Description was changed from

==========
Avoids WebRtcAudioTrack null pointer access at stop

Avoids WebRtcAudioTrack null pointer access at stop

BUG=
==========

to

==========
Avoids WebRtcAudioTrack null pointer access at stop.

BUG=b/64692432
==========

[henrika_webrtc, 2017-08-15 13:34:45]

henrika@webrtc.org changed reviewers:
+ glaznev@webrtc.org

[henrika_webrtc, 2017-08-15 13:39:32]

Description was changed from

==========
Avoids WebRtcAudioTrack null pointer access at stop.

BUG=b/64692432
==========

to

==========
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
==========

[henrika_webrtc, 2017-08-15 13:40:25]

PTAL

[henrika_webrtc, 2017-08-15 13:40:46]

The CQ bit was checked by henrika@webrtc.org to run a CQ dry run

[commit-bot: I haz the power, 2017-08-15 13:40:55]

Dry run: CQ is trying da patch.

Follow status at:
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.webrtc.org/...

[commit-bot: I haz the power, 2017-08-15 14:30:25]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2017-08-15 14:30:26]

Dry run: This issue passed the CQ dry run.

[AlexG, 2017-08-15 18:15:33]

lgtm

https://codereview.webrtc.org/3001703002/diff/1/webrtc/modules/audio_device/a...
File
webrtc/modules/audio_device/android/java/src/org/webrtc/voiceengine/WebRtcAudioTrack.java
(right):

https://codereview.webrtc.org/3001703002/diff/1/webrtc/modules/audio_device/a...
webrtc/modules/audio_device/android/java/src/org/webrtc/voiceengine/WebRtcAudioTrack.java:178:
audioTrack.flush();
May be still call audioTrack.stop() after flush()?

https://codereview.webrtc.org/3001703002/diff/1/webrtc/modules/audio_device/a...
webrtc/modules/audio_device/android/java/src/org/webrtc/voiceengine/WebRtcAudioTrack.java:443:
final AudioTrack at = audioTrack;
is this temporary variable necessary here?

[henrika_webrtc, 2017-08-16 11:25:16]

Thanks Alex. Landing. Please confirm on your side that things work as intended.

https://codereview.webrtc.org/3001703002/diff/1/webrtc/modules/audio_device/a...
File
webrtc/modules/audio_device/android/java/src/org/webrtc/voiceengine/WebRtcAudioTrack.java
(right):

https://codereview.webrtc.org/3001703002/diff/1/webrtc/modules/audio_device/a...
webrtc/modules/audio_device/android/java/src/org/webrtc/voiceengine/WebRtcAudioTrack.java:178:
audioTrack.flush();
The manual says, either use stop() for "slow stop" or pause()+flush() for "fast
stop" where the difference is that using stop() will wait for ongoing writes and
play that out as well. Given that we have seen issues
while closing it felt better to use the fast mode here. Also, the next step
after this section is to call audioTrack.release(). Hence, calling stop() here
as well is most likely a no-op.

But, perhaps I am changing too much as is since we no longer allow the playout
buffer to drain. So actually, I will change back to stop().

https://codereview.webrtc.org/3001703002/diff/1/webrtc/modules/audio_device/a...
webrtc/modules/audio_device/android/java/src/org/webrtc/voiceengine/WebRtcAudioTrack.java:443:
final AudioTrack at = audioTrack;
Probably not. Changing.

[henrika_webrtc, 2017-08-16 11:25:22]

The CQ bit was checked by henrika@webrtc.org

[henrika_webrtc, 2017-08-16 11:25:22]

The patchset sent to the CQ was uploaded after l-g-t-m from glaznev@webrtc.org
Link to the patchset: https://codereview.webrtc.org/3001703002/#ps20001 (title:
"Feedback from Alex")

[commit-bot: I haz the power, 2017-08-16 11:25:32]

CQ is trying da patch.

Follow status at:
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.webrtc.org/...

[commit-bot: I haz the power, 2017-08-16 13:14:08]

CQ is committing da patch.

Bot data: {"patchset_id": 20001, "attempt_start_ts": 1502882722545870,
"parent_rev": "7ea6e59735248059688bae7f6fad78112c38045f", "commit_rev":
"c103653113ebe6dbe11e7455c2c4f500c1fbbf8b"}

[commit-bot: I haz the power, 2017-08-16 13:14:12]

Description was changed from

==========
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
==========

to

==========
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}
Committed:
https://chromium.googlesource.com/external/webrtc/+/c103653113ebe6dbe11e7455c...
==========

[commit-bot: I haz the power, 2017-08-16 13:14:13]

Committed patchset #2 (id:20001) as
https://chromium.googlesource.com/external/webrtc/+/c103653113ebe6dbe11e7455c...