Preliminary change for new rtc rendering algorithm

Preliminary change for new rtc rendering algorithm:

1. Add trace flags for smoothness testing

2. Propagate render_time calculated in Jitter Buffer to media::VideoFrame for new rendering algorithm to use.

3. Move invalidation trigger to compositor thread.

This is a recommit of CL 1265433003, the original CL was reverted because it breaks Blink Layout tests and it crashes hangout for HW accelerated RTC.

BUG=514873, 525866, 525264
TBR=sunnyps@chromium.org,mcasas@chromium.org,dalecurtis@chromium.org,miu@chromium.org,piman@chromium.org

CQ_INCLUDE_TRYBOTS=tryserver.blink:linux_blink_rel;tryserver.blink:win_blink_rel

Committed: https://crrev.com/20e58fcd6465b008514601b5667390fffb1381fc
Cr-Commit-Position: refs/heads/master@{#348025}

[qiangchen, 2015-08-28 19:54:48]

qiangchen@chromium.org changed reviewers:
+ dalecurtis@chromium.org, niklase@chromium.org

[qiangchen, 2015-08-28 19:54:48]

CL was reverted because it crashes chrome in HW accelerated RTC. I found out the
reason is that we have to call CopyFrameToYV12 on the main thread.

[DaleCurtis, 2015-09-01 16:36:00]

This CL has been reverted 3 times now. I hope you'll take up my suggestion of
detangling a compositor type class with unittests after this lands :)

lgtm

[qiangchen, 2015-09-01 23:10:11]

On 2015/09/01 16:36:00, DaleCurtis wrote:
> This CL has been reverted 3 times now. I hope you'll take up my suggestion of
> detangling a compositor type class with unittests after this lands :)
> 
> lgtm

You are right, but only after those reverts, I can notice the checkpoints that
the unittest should guarantee.

[qiangchen, 2015-09-09 20:49:17]

The CQ bit was checked by qiangchen@chromium.org

[qiangchen, 2015-09-09 20:49:17]

The patchset sent to the CQ was uploaded after l-g-t-m from
dalecurtis@chromium.org
Link to the patchset: https://codereview.chromium.org/1320183003/#ps40001
(title: "Consider capture buffer contention")

[commit-bot: I haz the power, 2015-09-09 20:49:24]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1320183003/40001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1320183003/40001

[commit-bot: I haz the power, 2015-09-09 22:20:22]

Committed patchset #3 (id:40001)

[commit-bot: I haz the power, 2015-09-09 22:21:49]

Patchset 3 (id:??) landed as
https://crrev.com/20e58fcd6465b008514601b5667390fffb1381fc
Cr-Commit-Position: refs/heads/master@{#348025}

[commit-bot: I haz the power, 2015-09-23 12:04:17]

Patchset 3 (id:??) landed as
https://crrev.com/20e58fcd6465b008514601b5667390fffb1381fc
Cr-Commit-Position: refs/heads/master@{#348025}