Revert of Fix screen capturers to initialize on the same thread on which Start() is called.

Revert of Fix screen capturers to initialize on the same thread on which Start() is called. (patchset #3 id:80001 of https://codereview.webrtc.org/1861893002/ )

Reason for revert:
This is preventing a WebRTC roll into Chromium. See https://codereview.chromium.org/1877263003/

Original issue's description:
> Fix screen capturers to initialize on the same thread on which Start() is called.
>
> Previously screen capturers were initialized when they are created.
> This means that in the CRD host they were initialized on the thread
> that's different from the thread on which they are used. Because of this
> on Linux the host was using XErrorTrap() on two different threads and
> this is not supported. Now ScreenCapturer implementations always
> initialize themselves on the thread on which Start() is called.
>
> Also added ThreadChecker to make sure the capturers are always called
> from the same thread.
>
> BUG=600432
>
> Committed: https://crrev.com/e8d4b7d8a3d298438a2ebd9ee8d5aa71f42cf033
> Cr-Commit-Position: refs/heads/master@{#12285}

TBR=jamiewalch@chromium.org,sergeyu@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=600432
Committed: https://crrev.com/63911495de8bb001c3694c174bffdf5a85bb3ad1
Cr-Commit-Position: refs/heads/master@{#12334}

[guidou, 2016-04-12 13:31:01]

Created Revert of Fix screen capturers to initialize on the same thread on which
Start() is called.

[commit-bot: I haz the power, 2016-04-12 13:31:06]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1882083002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1882083002/1

[commit-bot: I haz the power, 2016-04-12 13:32:00]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1882083002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1882083002/1

[commit-bot: I haz the power, 2016-04-12 13:38:09]

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

[commit-bot: I haz the power, 2016-04-12 13:38:10]

Try jobs failed on following builders:
  win_drmemory_light on tryserver.webrtc (JOB_FAILED,
http://build.chromium.org/p/tryserver.webrtc/builders/win_drmemory_light/buil...)

[guidou, 2016-04-12 14:15:03]

The CQ bit was checked by guidou@webrtc.org

[commit-bot: I haz the power, 2016-04-12 14:15:06]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1882083002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1882083002/1

[commit-bot: I haz the power, 2016-04-12 15:32:02]

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

[commit-bot: I haz the power, 2016-04-12 15:32:03]

Try jobs failed on following builders:
  android_arm64_rel on tryserver.webrtc (JOB_TIMED_OUT, no build URL)
  linux_baremetal on tryserver.webrtc (JOB_TIMED_OUT, no build URL)
  win_baremetal on tryserver.webrtc (JOB_TIMED_OUT, no build URL)

[guidou, 2016-04-12 17:08:55]

The CQ bit was checked by guidou@webrtc.org

[commit-bot: I haz the power, 2016-04-12 17:09:05]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1882083002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1882083002/1

[Guido Urdaneta, 2016-04-12 18:03:47]

The CQ bit was unchecked by guidou@chromium.org

[Guido Urdaneta, 2016-04-12 18:04:14]

The CQ bit was checked by guidou@chromium.org

[commit-bot: I haz the power, 2016-04-12 18:04:25]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1882083002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1882083002/1

[commit-bot: I haz the power, 2016-04-12 18:42:05]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-04-12 18:42:10]

Description was changed from

==========
Revert of Fix screen capturers to initialize on the same thread on which Start()
is called. (patchset #3 id:80001 of https://codereview.webrtc.org/1861893002/ )

Reason for revert:
This is preventing a WebRTC roll into Chromium. See
https://codereview.chromium.org/1877263003/

Original issue's description:
> Fix screen capturers to initialize on the same thread on which Start() is
called.
> 
> Previously screen capturers were initialized when they are created.
> This means that in the CRD host they were initialized on the thread
> that's different from the thread on which they are used. Because of this
> on Linux the host was using XErrorTrap() on two different threads and
> this is not supported. Now ScreenCapturer implementations always
> initialize themselves on the thread on which Start() is called.
> 
> Also added ThreadChecker to make sure the capturers are always called
> from the same thread.
> 
> BUG=600432
> 
> Committed: https://crrev.com/e8d4b7d8a3d298438a2ebd9ee8d5aa71f42cf033
> Cr-Commit-Position: refs/heads/master@{#12285}

TBR=jamiewalch@chromium.org,sergeyu@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=600432
==========

to

==========
Revert of Fix screen capturers to initialize on the same thread on which Start()
is called. (patchset #3 id:80001 of https://codereview.webrtc.org/1861893002/ )

Reason for revert:
This is preventing a WebRTC roll into Chromium. See
https://codereview.chromium.org/1877263003/

Original issue's description:
> Fix screen capturers to initialize on the same thread on which Start() is
called.
>
> Previously screen capturers were initialized when they are created.
> This means that in the CRD host they were initialized on the thread
> that's different from the thread on which they are used. Because of this
> on Linux the host was using XErrorTrap() on two different threads and
> this is not supported. Now ScreenCapturer implementations always
> initialize themselves on the thread on which Start() is called.
>
> Also added ThreadChecker to make sure the capturers are always called
> from the same thread.
>
> BUG=600432
>
> Committed: https://crrev.com/e8d4b7d8a3d298438a2ebd9ee8d5aa71f42cf033
> Cr-Commit-Position: refs/heads/master@{#12285}

TBR=jamiewalch@chromium.org,sergeyu@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=600432

Committed: https://crrev.com/63911495de8bb001c3694c174bffdf5a85bb3ad1
Cr-Commit-Position: refs/heads/master@{#12334}
==========

[commit-bot: I haz the power, 2016-04-12 18:42:11]

Patchset 1 (id:??) landed as
https://crrev.com/63911495de8bb001c3694c174bffdf5a85bb3ad1
Cr-Commit-Position: refs/heads/master@{#12334}