New FRAME_DURATION VideoFrameMetadata, with Cast Streaming use case.

New FRAME_DURATION VideoFrameMetadata, with Cast Streaming use case.

Adds a new FRAME_DURATION option to VideoFrameMetadata, which can be
used by consumers of video frames to improve performance (e.g., encoding
quality).

This change also adds population of the new metadata by the desktop/tab
capture pipeline, and consumption by Cast Streaming's software VP8
encoder.  Having accurate frame duration information improves the
encoder's ability to choose a compression quality level that better
meets the target encode bitrate.

Later changes will require this in order to compute resource utilization
feedback signals (see bug for details).

BUG=156767
Committed: https://crrev.com/1cb99158245ac2a36ea0ee5e20fd2fff71c864d1
Cr-Commit-Position: refs/heads/master@{#330661}

[miu, 2015-05-19 04:45:48]

Patchset #1 (id:1) has been deleted

[miu, 2015-05-19 04:46:34]

miu@chromium.org changed reviewers:
+ hubbe@chromium.org

[miu, 2015-05-19 04:46:34]

hubbe: PTAL.

[hubbe, 2015-05-19 17:58:32]

https://codereview.chromium.org/1146723002/diff/20001/media/base/video_frame_...
File media/base/video_frame_metadata.h (right):

https://codereview.chromium.org/1146723002/diff/20001/media/base/video_frame_...
media/base/video_frame_metadata.h:27: FRAME_DURATION,
I think some additional explanation is needed.
I mean, isn't FRAME_DURATION equal to 1/FRAME_RATE ?

[miu, 2015-05-19 20:14:52]

https://codereview.chromium.org/1146723002/diff/20001/media/base/video_frame_...
File media/base/video_frame_metadata.h (right):

https://codereview.chromium.org/1146723002/diff/20001/media/base/video_frame_...
media/base/video_frame_metadata.h:27: FRAME_DURATION,
On 2015/05/19 17:58:32, hubbe wrote:
> I think some additional explanation is needed.
> I mean, isn't FRAME_DURATION equal to 1/FRAME_RATE ?

Done.

[hubbe, 2015-05-19 20:28:51]

lgtm

[miu, 2015-05-19 20:40:53]

miu@chromium.org changed reviewers:
+ dalecurtis@chromium.org

[miu, 2015-05-19 20:40:54]

dalecurtis: PTAL for media/ OWNERS approval.

[DaleCurtis, 2015-05-19 23:31:32]

lgtm

[miu, 2015-05-19 23:36:39]

The CQ bit was checked by miu@chromium.org

[commit-bot: I haz the power, 2015-05-20 00:22:14]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1146723002/40001

[commit-bot: I haz the power, 2015-05-20 00:31:43]

Committed patchset #2 (id:40001)

[commit-bot: I haz the power, 2015-05-20 00:32:33]

Patchset 2 (id:??) landed as
https://crrev.com/1cb99158245ac2a36ea0ee5e20fd2fff71c864d1
Cr-Commit-Position: refs/heads/master@{#330661}