Revert of cc: Remove frame queuing from the scheduler.

Revert of cc: Remove frame queuing from the scheduler. (patchset #14 id:400001 of https://codereview.chromium.org/2339633003/ )

Reason for revert:
Highly likely that this is causing the flakes we are seeing in http://crbug.com/645736

Original issue's description:
> Reland of cc: Remove frame queuing from the scheduler. (patchset #1 id:1 of https://codereview.chromium.org/2336493002/ )
> 
> Reason for revert:
> Reland after fixing screenshot grabber test and perf issues.
> 
> Original issue's description:
> > Revert of cc: Remove frame queuing from the scheduler. (patchset #3 id:40001 of https://codereview.chromium.org/2323063004/ )
> >
> > Reason for revert:
> > Broke ChromeScreenshotGrabberTest.TakeScreenshot on  Linux ChromiumOS Tests (dbg)(1): https://build.chromium.org/p/chromium.chromiumos/builders/Linux%20ChromiumOS%20Tests%20%28dbg%29%281%29/builds/18015.
> >
> > Original issue's description:
> > > cc: Remove frame queuing from the scheduler.
> > >
> > > CC scheduler has a frame queuing mechanism called "retro frames". This
> > > has been responsible for a lot of complexity and hard to fix bugs. The
> > > original intent for adding retro frames was to allow the scheduler to
> > > handle multiple frames in flight but that goal doesn't seem feasible or
> > > even desirable any more. This CL removes the retro frames queue and
> > > instead makes the Scheduler end the previous frame when it receives a
> > > BeginFrame message.
> > >
> > > One surprising behavior was that SyntheticBFS MISSED frames would be
> > > queued as retro frames and this would convert the synchronous begin
> > > frame call (inside Scheduler::ProcessScheduledActions) to an
> > > asynchronous retro frame PostTask. To work around this the Scheduler
> > > keeps track of a single CancelableClosure that's used for MISSED frames.
> > >
> > > The above behavior was also causing the BeginFramesNotFromClient tests
> > > to work even though there was an extra MISSED frame in the queue. This
> > > is more elegantly solved in another way by using frame number to advance
> > > the task runner instead of just running pending tasks.
> > >
> > > Lastly SchedulerStateMachine is modified so that it's possible to end
> > > the previous frame and still have the same behavior as before in the
> > > commit to active tree (browser compositor) mode.
> > >
> > > R=brianderson@chromium.org,enne@chromium.org,danakj@chromium.org
> > > BUG=602485, 644992
> > > CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_precise_blink_rel
> > >
> > > Committed: https://crrev.com/559280b26cc5672f5f054e8ac35281e804c14d78
> > > Cr-Commit-Position: refs/heads/master@{#417764}
> >
> > TBR=enne@chromium.org,brianderson@chromium.org,danakj@chromium.org,sunnyps@chromium.org
> > # Not skipping CQ checks because original CL landed more than 1 days ago.
> > BUG=602485, 644992
> >
> > Committed: https://crrev.com/95beb47e50065959ee2f5b43cf431431e32e14cd
> > Cr-Commit-Position: refs/heads/master@{#417895}
> 
> TBR=enne@chromium.org,brianderson@chromium.org,danakj@chromium.org,sammc@chromium.org
> # Not skipping CQ checks because original CL landed more than 1 days ago.
> BUG=602485, 644992
> CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_precise_blink_rel
> 
> Committed: https://crrev.com/864a70f6f93a87ff374bf2aea2494d4d7d0150d7
> Cr-Commit-Position: refs/heads/master@{#421268}

TBR=enne@chromium.org,danakj@chromium.org,sunnyps@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=602485, 644992

[brianderson, 2016-09-30 23:44:38]

The CQ bit was checked by brianderson@chromium.org

[brianderson, 2016-09-30 23:44:38]

Created Revert of cc: Remove frame queuing from the scheduler.

[commit-bot: I haz the power, 2016-09-30 23:45:40]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-09-30 23:48:46]

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

[commit-bot: I haz the power, 2016-09-30 23:48:47]

Try jobs failed on following builders:
  ios-device on master.tryserver.chromium.mac (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.mac/builders/ios-device/builds...)
  ios-simulator on master.tryserver.chromium.mac (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.mac/builders/ios-simulator/bui...)
  mac_chromium_compile_dbg_ng on master.tryserver.chromium.mac (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.mac/builders/mac_chromium_comp...)

[sunnyps, 2016-10-03 20:26:46]

I fixed the conflicts and uploaded a new revert here:
https://codereview.chromium.org/2386183003

[sunnyps, 2016-10-03 20:26:57]

Description was changed from

==========
Revert of cc: Remove frame queuing from the scheduler. (patchset #14 id:400001
of https://codereview.chromium.org/2339633003/ )

Reason for revert:
Highly likely that this is causing the flakes we are seeing in
http://crbug.com/645736

Original issue's description:
> Reland of cc: Remove frame queuing from the scheduler. (patchset #1 id:1 of
https://codereview.chromium.org/2336493002/ )
> 
> Reason for revert:
> Reland after fixing screenshot grabber test and perf issues.
> 
> Original issue's description:
> > Revert of cc: Remove frame queuing from the scheduler. (patchset #3 id:40001
of https://codereview.chromium.org/2323063004/ )
> >
> > Reason for revert:
> > Broke ChromeScreenshotGrabberTest.TakeScreenshot on  Linux ChromiumOS Tests
(dbg)(1):
https://build.chromium.org/p/chromium.chromiumos/builders/Linux%20ChromiumOS%....
> >
> > Original issue's description:
> > > cc: Remove frame queuing from the scheduler.
> > >
> > > CC scheduler has a frame queuing mechanism called "retro frames". This
> > > has been responsible for a lot of complexity and hard to fix bugs. The
> > > original intent for adding retro frames was to allow the scheduler to
> > > handle multiple frames in flight but that goal doesn't seem feasible or
> > > even desirable any more. This CL removes the retro frames queue and
> > > instead makes the Scheduler end the previous frame when it receives a
> > > BeginFrame message.
> > >
> > > One surprising behavior was that SyntheticBFS MISSED frames would be
> > > queued as retro frames and this would convert the synchronous begin
> > > frame call (inside Scheduler::ProcessScheduledActions) to an
> > > asynchronous retro frame PostTask. To work around this the Scheduler
> > > keeps track of a single CancelableClosure that's used for MISSED frames.
> > >
> > > The above behavior was also causing the BeginFramesNotFromClient tests
> > > to work even though there was an extra MISSED frame in the queue. This
> > > is more elegantly solved in another way by using frame number to advance
> > > the task runner instead of just running pending tasks.
> > >
> > > Lastly SchedulerStateMachine is modified so that it's possible to end
> > > the previous frame and still have the same behavior as before in the
> > > commit to active tree (browser compositor) mode.
> > >
> > > R=brianderson@chromium.org,enne@chromium.org,danakj@chromium.org
> > > BUG=602485, 644992
> > > CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_precise_blink_rel
> > >
> > > Committed: https://crrev.com/559280b26cc5672f5f054e8ac35281e804c14d78
> > > Cr-Commit-Position: refs/heads/master@{#417764}
> >
> >
TBR=enne@chromium.org,brianderson@chromium.org,danakj@chromium.org,sunnyps@ch...
> > # Not skipping CQ checks because original CL landed more than 1 days ago.
> > BUG=602485, 644992
> >
> > Committed: https://crrev.com/95beb47e50065959ee2f5b43cf431431e32e14cd
> > Cr-Commit-Position: refs/heads/master@{#417895}
> 
>
TBR=enne@chromium.org,brianderson@chromium.org,danakj@chromium.org,sammc@chro...
> # Not skipping CQ checks because original CL landed more than 1 days ago.
> BUG=602485, 644992
> CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_precise_blink_rel
> 
> Committed: https://crrev.com/864a70f6f93a87ff374bf2aea2494d4d7d0150d7
> Cr-Commit-Position: refs/heads/master@{#421268}

TBR=enne@chromium.org,danakj@chromium.org,sunnyps@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=602485, 644992
==========

to

==========
Revert of cc: Remove frame queuing from the scheduler. (patchset #14 id:400001
of https://codereview.chromium.org/2339633003/ )

Reason for revert:
Highly likely that this is causing the flakes we are seeing in
http://crbug.com/645736

Original issue's description:
> Reland of cc: Remove frame queuing from the scheduler. (patchset #1 id:1 of
https://codereview.chromium.org/2336493002/ )
> 
> Reason for revert:
> Reland after fixing screenshot grabber test and perf issues.
> 
> Original issue's description:
> > Revert of cc: Remove frame queuing from the scheduler. (patchset #3 id:40001
of https://codereview.chromium.org/2323063004/ )
> >
> > Reason for revert:
> > Broke ChromeScreenshotGrabberTest.TakeScreenshot on  Linux ChromiumOS Tests
(dbg)(1):
https://build.chromium.org/p/chromium.chromiumos/builders/Linux%20ChromiumOS%....
> >
> > Original issue's description:
> > > cc: Remove frame queuing from the scheduler.
> > >
> > > CC scheduler has a frame queuing mechanism called "retro frames". This
> > > has been responsible for a lot of complexity and hard to fix bugs. The
> > > original intent for adding retro frames was to allow the scheduler to
> > > handle multiple frames in flight but that goal doesn't seem feasible or
> > > even desirable any more. This CL removes the retro frames queue and
> > > instead makes the Scheduler end the previous frame when it receives a
> > > BeginFrame message.
> > >
> > > One surprising behavior was that SyntheticBFS MISSED frames would be
> > > queued as retro frames and this would convert the synchronous begin
> > > frame call (inside Scheduler::ProcessScheduledActions) to an
> > > asynchronous retro frame PostTask. To work around this the Scheduler
> > > keeps track of a single CancelableClosure that's used for MISSED frames.
> > >
> > > The above behavior was also causing the BeginFramesNotFromClient tests
> > > to work even though there was an extra MISSED frame in the queue. This
> > > is more elegantly solved in another way by using frame number to advance
> > > the task runner instead of just running pending tasks.
> > >
> > > Lastly SchedulerStateMachine is modified so that it's possible to end
> > > the previous frame and still have the same behavior as before in the
> > > commit to active tree (browser compositor) mode.
> > >
> > > R=brianderson@chromium.org,enne@chromium.org,danakj@chromium.org
> > > BUG=602485, 644992
> > > CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_precise_blink_rel
> > >
> > > Committed: https://crrev.com/559280b26cc5672f5f054e8ac35281e804c14d78
> > > Cr-Commit-Position: refs/heads/master@{#417764}
> >
> >
TBR=enne@chromium.org,brianderson@chromium.org,danakj@chromium.org,sunnyps@ch...
> > # Not skipping CQ checks because original CL landed more than 1 days ago.
> > BUG=602485, 644992
> >
> > Committed: https://crrev.com/95beb47e50065959ee2f5b43cf431431e32e14cd
> > Cr-Commit-Position: refs/heads/master@{#417895}
> 
>
TBR=enne@chromium.org,brianderson@chromium.org,danakj@chromium.org,sammc@chro...
> # Not skipping CQ checks because original CL landed more than 1 days ago.
> BUG=602485, 644992
> CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_precise_blink_rel
> 
> Committed: https://crrev.com/864a70f6f93a87ff374bf2aea2494d4d7d0150d7
> Cr-Commit-Position: refs/heads/master@{#421268}

TBR=enne@chromium.org,danakj@chromium.org,sunnyps@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=602485, 644992
==========