Refactor external begin frame source into a base class

Refactor external begin frame source into a base class

There are several external begin frame sources in the code base,
and they all have the same logic.  mus will need another.  So,
refactor this logic into a base class that they all can reuse.

The followup to this will be to make Android's CompositorImpl's
ExternalBeginFrameSource derive from cc::ExternalBeginFrameSource.

R=danakj@chromium.org
CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_precise_blink_rel

Committed: https://crrev.com/8b4aaaae53d89639fbebde0cfb8b7eeb73861fa5
Cr-Commit-Position: refs/heads/master@{#414927}

[enne (OOO), 2016-08-26 18:54:02]

Description was changed from

==========
Refactor external begin frame source into a base class

There are several external begin frame sources in the code base,
and they all have the same logic.  mus will need another.  So,
refactor this logic into a base class that they all can reuse.

The followup to this will be to make Android's CompositorImpl's
ExternalBeginFrameSource derive from cc::ExternalBeginFrameSource.

R=danakj@chromium.org
==========

to

==========
Refactor external begin frame source into a base class

There are several external begin frame sources in the code base,
and they all have the same logic.  mus will need another.  So,
refactor this logic into a base class that they all can reuse.

The followup to this will be to make Android's CompositorImpl's
ExternalBeginFrameSource derive from cc::ExternalBeginFrameSource.

R=danakj@chromium.org
CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_precise_blink_rel
==========

[enne (OOO), 2016-08-26 18:55:12]

The CQ bit was checked by enne@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2016-08-26 18:56:08]

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

[enne (OOO), 2016-08-26 20:34:45]

The CQ bit was checked by enne@chromium.org to run a CQ dry run

[enne (OOO), 2016-08-26 20:34:56]

Maybe you'll like this version better.

[commit-bot: I haz the power, 2016-08-26 20:35:40]

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

[danakj, 2016-08-26 22:39:13]

LGTM

https://codereview.chromium.org/2281143002/diff/20001/cc/scheduler/begin_fram...
File cc/scheduler/begin_frame_source.cc (right):

https://codereview.chromium.org/2281143002/diff/20001/cc/scheduler/begin_fram...
cc/scheduler/begin_frame_source.cc:187:
ExternalBeginFrameSource::~ExternalBeginFrameSource() {}
= default

https://codereview.chromium.org/2281143002/diff/20001/cc/scheduler/begin_fram...
File cc/scheduler/begin_frame_source.h (right):

https://codereview.chromium.org/2281143002/diff/20001/cc/scheduler/begin_fram...
cc/scheduler/begin_frame_source.h:210: // A begin frame source that is only
ticked manually.  Usually the endpoint
"A BeginFrameSource"

https://codereview.chromium.org/2281143002/diff/20001/cc/scheduler/begin_fram...
cc/scheduler/begin_frame_source.h:229: protected:
private?

https://codereview.chromium.org/2281143002/diff/20001/content/renderer/gpu/co...
File content/renderer/gpu/compositor_external_begin_frame_source.h (right):

https://codereview.chromium.org/2281143002/diff/20001/content/renderer/gpu/co...
content/renderer/gpu/compositor_external_begin_frame_source.h:26: : public
cc::BeginFrameSource,
Can we TODO to remove this as a subclass and explain future plans?

https://codereview.chromium.org/2281143002/diff/20001/content/renderer/gpu/co...
content/renderer/gpu/compositor_external_begin_frame_source.h:42: //
cc::ExternalBeginFrameSourceClient implementation
.

[commit-bot: I haz the power, 2016-08-26 22:53:13]

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

[commit-bot: I haz the power, 2016-08-26 22:53:14]

Dry run: This issue passed the CQ dry run.

[enne (OOO), 2016-08-27 00:09:58]

The CQ bit was checked by enne@chromium.org

[enne (OOO), 2016-08-27 00:09:58]

The patchset sent to the CQ was uploaded after l-g-t-m from danakj@chromium.org
Link to the patchset: https://codereview.chromium.org/2281143002/#ps40001
(title: "danakj review")

[commit-bot: I haz the power, 2016-08-27 00:11:08]

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, 2016-08-27 11:11:35]

Committed patchset #3 (id:40001)

[commit-bot: I haz the power, 2016-08-27 11:13:17]

Description was changed from

==========
Refactor external begin frame source into a base class

There are several external begin frame sources in the code base,
and they all have the same logic.  mus will need another.  So,
refactor this logic into a base class that they all can reuse.

The followup to this will be to make Android's CompositorImpl's
ExternalBeginFrameSource derive from cc::ExternalBeginFrameSource.

R=danakj@chromium.org
CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_precise_blink_rel
==========

to

==========
Refactor external begin frame source into a base class

There are several external begin frame sources in the code base,
and they all have the same logic.  mus will need another.  So,
refactor this logic into a base class that they all can reuse.

The followup to this will be to make Android's CompositorImpl's
ExternalBeginFrameSource derive from cc::ExternalBeginFrameSource.

R=danakj@chromium.org
CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_precise_blink_rel

Committed: https://crrev.com/8b4aaaae53d89639fbebde0cfb8b7eeb73861fa5
Cr-Commit-Position: refs/heads/master@{#414927}
==========

[commit-bot: I haz the power, 2016-08-27 11:13:18]

Patchset 3 (id:??) landed as
https://crrev.com/8b4aaaae53d89639fbebde0cfb8b7eeb73861fa5
Cr-Commit-Position: refs/heads/master@{#414927}