Remove a thread checker for a decoder thread from IncomingVideoStream.

Remove a thread checker for a decoder thread from IncomingVideoStream.
The specific decoder thread may vary when using VideoToolbox.

BUG=webrtc:6051
TBR=pbos@webrtc.org

Committed: https://crrev.com/7893e9a267769940d6fd4276196208ee91d7afbf
Cr-Commit-Position: refs/heads/master@{#13292}

[tommi, 2016-06-27 07:49:10]

The CQ bit was checked by tommi@webrtc.org

[commit-bot: I haz the power, 2016-06-27 07:49:18]

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, 2016-06-27 07:52:51]

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

[commit-bot: I haz the power, 2016-06-27 07:52:52]

Try jobs failed on following builders:
  android_arm64_rel on tryserver.webrtc (JOB_FAILED,
http://build.chromium.org/p/tryserver.webrtc/builders/android_arm64_rel/build...)
  android_dbg on tryserver.webrtc (JOB_FAILED,
http://build.chromium.org/p/tryserver.webrtc/builders/android_dbg/builds/14478)

[tommi, 2016-06-27 07:55:03]

Description was changed from

==========
Remove a thread checker for a decoder thread from IncomingVideoStream.
The specific decoder thread may vary when using VideoToolbox.

BUG=webrtc:6051
TBR=pbos@webrtc.org
==========

to

==========
Remove a thread checker for a decoder thread from IncomingVideoStream.
The specific decoder thread may vary when using VideoToolbox.

BUG=webrtc:6051
TBR=pbos@webrtc.org

Committed:
https://chromium.googlesource.com/external/webrtc/+/7893e9a267769940d6fd42761...
==========

[tommi, 2016-06-27 07:55:05]

Committed patchset #1 (id:1) manually as
7893e9a267769940d6fd4276196208ee91d7afbf (presubmit successful).

[commit-bot: I haz the power, 2016-06-27 07:55:07]

Description was changed from

==========
Remove a thread checker for a decoder thread from IncomingVideoStream.
The specific decoder thread may vary when using VideoToolbox.

BUG=webrtc:6051
TBR=pbos@webrtc.org

Committed:
https://chromium.googlesource.com/external/webrtc/+/7893e9a267769940d6fd42761...
==========

to

==========
Remove a thread checker for a decoder thread from IncomingVideoStream.
The specific decoder thread may vary when using VideoToolbox.

BUG=webrtc:6051
TBR=pbos@webrtc.org

Committed: https://crrev.com/7893e9a267769940d6fd4276196208ee91d7afbf
Cr-Commit-Position: refs/heads/master@{#13292}
==========

[sakal, 2016-06-27 13:03:19]

I would like to note this was affecting Android as well. See bug:
https://bugs.chromium.org/p/webrtc/issues/detail?id=5999

[pbos-webrtc, 2016-06-27 15:17:30]

lgtm