WIP: Towards merging OffscreenCanvas and Mus code

WIP: Towards merging OffscreenCanvas and Mus code

BUG=

[xlai (Olivia), 2017-02-13 20:37:10]

Description was changed from

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WIP: Towards merging OffscreenCanvas and Mus code

BUG=
==========

to

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WIP: Towards merging OffscreenCanvas and Mus code

BUG=
==========

[Fady Samuel, 2017-02-15 16:44:15]

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

[commit-bot: I haz the power, 2017-02-15 16:44:56]

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

[Fady Samuel, 2017-02-15 16:49:27]

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

[commit-bot: I haz the power, 2017-02-15 16:49:52]

Dry run: 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, 2017-02-15 17:11:41]

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

[commit-bot: I haz the power, 2017-02-15 17:11:42]

Dry run: Try jobs failed on following builders:
  linux_chromium_chromeos_rel_ng on master.tryserver.chromium.linux (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...)
  linux_chromium_compile_dbg_ng on master.tryserver.chromium.linux (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...)

[Fady Samuel, 2017-02-15 18:48:36]

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

[commit-bot: I haz the power, 2017-02-15 18:50:28]

Dry run: 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, 2017-02-15 19:01:37]

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

[commit-bot: I haz the power, 2017-02-15 19:01:38]

Dry run: Try jobs failed on following builders:
  chromeos_daisy_chromium_compile_only_ng on master.tryserver.chromium.linux
(JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.linux/builders/chromeos_daisy_...)
  win_chromium_compile_dbg_ng on master.tryserver.chromium.win (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.win/builders/win_chromium_comp...)
  win_chromium_rel_ng on master.tryserver.chromium.win (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.win/builders/win_chromium_rel_...)
  win_clang on master.tryserver.chromium.win (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.win/builders/win_clang/builds/...)

[Fady Samuel, 2017-02-15 20:30:03]

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

[commit-bot: I haz the power, 2017-02-15 20:31:09]

Dry run: 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, 2017-02-15 21:14:34]

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

[commit-bot: I haz the power, 2017-02-15 21:14:35]

Dry run: Try jobs failed on following builders:
  win_clang on master.tryserver.chromium.win (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.win/builders/win_clang/builds/...)

[Fady Samuel, 2017-02-16 04:26:50]

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

[commit-bot: I haz the power, 2017-02-16 04:27:39]

Dry run: 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, 2017-02-16 04:53:53]

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

[commit-bot: I haz the power, 2017-02-16 04:53:57]

Dry run: Try jobs failed on following builders:
  mac_chromium_compile_dbg_ng on master.tryserver.chromium.mac (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.mac/builders/mac_chromium_comp...)

[Fady Samuel, 2017-02-16 18:50:09]

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

[commit-bot: I haz the power, 2017-02-16 18:51:40]

Dry run: 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, 2017-02-16 19:25:38]

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

[commit-bot: I haz the power, 2017-02-16 19:25:39]

Dry run: Try jobs failed on following builders:
  win_chromium_compile_dbg_ng on master.tryserver.chromium.win (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.win/builders/win_chromium_comp...)

[Fady Samuel, 2017-02-16 20:37:26]

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

[commit-bot: I haz the power, 2017-02-16 20:38:28]

Dry run: 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, 2017-02-16 21:15:27]

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

[commit-bot: I haz the power, 2017-02-16 21:15:29]

Dry run: Try jobs failed on following builders:
  cast_shell_linux on master.tryserver.chromium.linux (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.linux/builders/cast_shell_linu...)

[Fady Samuel, 2017-02-17 17:58:53]

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

[commit-bot: I haz the power, 2017-02-17 17:59:24]

Dry run: 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, 2017-02-17 18:30:03]

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

[commit-bot: I haz the power, 2017-02-17 18:30:05]

Dry run: Try jobs failed on following builders:
  mac_chromium_compile_dbg_ng on master.tryserver.chromium.mac (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.mac/builders/mac_chromium_comp...)

[xing.xu, 2017-02-20 02:36:51]

Hi, Fady, I am also working on moving offscreen canvas into new display
compositor in non-USE_AURA: https://codereview.chromium.org/2703503002/
The key issue I didn't resolve is, OffscreenCanvas requires a BeginFrameSource.
if not provided, will fail OffscreenCanvas-commit-promise.html.
For non-display compositor based offscreen canvas, BeginFrameSource is provided
by WebLayerTreeView.
For my cl, I am still working on how to setup this BeginFrameSource for
OffscreenCanvas.
So does it worth to try to move offscreen canvas into new display compositor in
non-USE_AURA first?

[Fady Samuel, 2017-02-20 17:32:10]

On 2017/02/20 02:36:51, xing.xu wrote:
> Hi, Fady, I am also working on moving offscreen canvas into new display
> compositor in non-USE_AURA: https://codereview.chromium.org/2703503002/
> The key issue I didn't resolve is, OffscreenCanvas requires a
BeginFrameSource.
> if not provided, will fail OffscreenCanvas-commit-promise.html.
> For non-display compositor based offscreen canvas, BeginFrameSource is
provided
> by WebLayerTreeView.
> For my cl, I am still working on how to setup this BeginFrameSource for
> OffscreenCanvas.
> So does it worth to try to move offscreen canvas into new display compositor
in
> non-USE_AURA first?

Hi Xing! This is cool! Feel free to pick up this CL if you'd like to continue
work on it. Please let me know if you have any questions. 

The key point here is the display compositor is not responsible for setting up
the BeginFrame hierarchy here. The browser process or window server on mus is.

The way we set up the BeginFrame hierarchy for offscreen canvas today is fine.
We can have a separate code path for Mus+Ash.

Ultimately, I want to delete OffscreenCanvasCompositorFrameSink. I want the
browser process to use the same DisplayCompositor code as Mus+Ash, for now.
OffscreenCanvas is created in an unprivileged process, so it should go to the
browser process to request a CompositorFrameSink which then uses the
DisplayCompositor interface to request a CompositorFrameSink.