cc: Add support for handling authoritative vsync interval

cc: Add support for handling authoritative vsync interval

This is partial cl from https://codereview.chromium.org/775143003/
for easy reviewing.
For now, authoritative vsync interval is handled by CompositorVsyncManager.
It will not be used when BeginFrame scheduling is enabled on aura.
Instead, it will be handled by scheduler.
In the next cl, BeginFrame sheduling on aura(and ash) will be turned on.

R=brianderson@chromium.org, mithro@mithis.com
BUG=372086
TEST=cc_unittests

Committed: https://crrev.com/298590fea3aa0a7dc68bc4d3753baad106001bc4
Cr-Commit-Position: refs/heads/master@{#322125}

[simonhong, 2015-03-24 15:00:37]

PTAL!

[simonhong, 2015-03-24 15:01:28]

simonhong@chromium.org changed reviewers:
+ mithro@mithis.com

[brianderson, 2015-03-25 01:16:55]

To verify, the intent of this patch is to only allow the scheduler to handle the
authoritative vsync interval. But it won't actually handle the authoritative
vsync interval until the BeginFrame message is turned on for Aura and
CompositorVSyncManager is used?

If so, lgtm.

[simonhong, 2015-03-25 02:04:14]

On 2015/03/25 01:16:55, brianderson wrote:
> To verify, the intent of this patch is to only allow the scheduler to handle
the
> authoritative vsync interval. But it won't actually handle the authoritative
> vsync interval until the BeginFrame message is turned on for Aura and
> CompositorVSyncManager is used?
> 
> If so, lgtm.

Yes, right.
This facility is enabled by the next patch.

[simonhong, 2015-03-25 02:04:24]

The CQ bit was checked by simonhong@chromium.org

[commit-bot: I haz the power, 2015-03-25 02:05:16]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1005553004/1

[commit-bot: I haz the power, 2015-03-25 04:45:40]

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

[commit-bot: I haz the power, 2015-03-25 04:45:41]

Try jobs failed on following builders:
  linux_chromium_chromeos_ozone_rel_ng on tryserver.chromium.linux (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...)

[simonhong, 2015-03-25 05:22:30]

The CQ bit was checked by simonhong@chromium.org

[commit-bot: I haz the power, 2015-03-25 05:22:49]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1005553004/1

[commit-bot: I haz the power, 2015-03-25 06:51:27]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-03-25 06:51:49]

Patchset 1 (id:??) landed as
https://crrev.com/298590fea3aa0a7dc68bc4d3753baad106001bc4
Cr-Commit-Position: refs/heads/master@{#322125}