Add non-blocking frame rate limiting logic to display list 2D canvas

Add non-blocking frame rate limiting logic to display list 2D canvas

This patch inserts frame barriers at the end of script execution tasks
that draw to a canvas. This is to prevent the accumulation of a multi-
frame backlog of draw commands in the SkPicture used by the display
list canvas implementation.

BUG=397516
TEST=RecordingImageBufferSurface unit tests

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=179175

[Justin Novosad, 2014-07-29 18:24:22]

PTAL

[Stephen White, 2014-07-29 18:38:55]

Kudos for mocking Platform. :)

https://codereview.chromium.org/429643002/diff/1/Source/platform/graphics/Rec...
File Source/platform/graphics/RecordingImageBufferSurface.cpp (right):

https://codereview.chromium.org/429643002/diff/1/Source/platform/graphics/Rec...
Source/platform/graphics/RecordingImageBufferSurface.cpp:154: return
!canvasIsAnimated;
Is this more like "canvas has changed"? I.e., something got drawn?

Maybe "canvasHasChanged" or "canvasWasRecordedTo" or "canvasWasDrawnTo"?

Or even just a non-m_ version of what it's copying, so
recordedSinceLastFrameWasFinalized?

https://codereview.chromium.org/429643002/diff/1/Source/platform/graphics/Rec...
File Source/platform/graphics/RecordingImageBufferSurfaceTest.cpp (right):

https://codereview.chromium.org/429643002/diff/1/Source/platform/graphics/Rec...
Source/platform/graphics/RecordingImageBufferSurfaceTest.cpp:131: // for the
current thread. The Mock thread is capable of queuing a single non-delyaed task
Nit: non-delayed

[Stephen White, 2014-07-29 18:39:08]

On 2014/07/29 18:38:55, Stephen White wrote:
> Kudos for mocking Platform. :)
> 
>
https://codereview.chromium.org/429643002/diff/1/Source/platform/graphics/Rec...
> File Source/platform/graphics/RecordingImageBufferSurface.cpp (right):
> 
>
https://codereview.chromium.org/429643002/diff/1/Source/platform/graphics/Rec...
> Source/platform/graphics/RecordingImageBufferSurface.cpp:154: return
> !canvasIsAnimated;
> Is this more like "canvas has changed"? I.e., something got drawn?
> 
> Maybe "canvasHasChanged" or "canvasWasRecordedTo" or "canvasWasDrawnTo"?
> 
> Or even just a non-m_ version of what it's copying, so
> recordedSinceLastFrameWasFinalized?
> 
>
https://codereview.chromium.org/429643002/diff/1/Source/platform/graphics/Rec...
> File Source/platform/graphics/RecordingImageBufferSurfaceTest.cpp (right):
> 
>
https://codereview.chromium.org/429643002/diff/1/Source/platform/graphics/Rec...
> Source/platform/graphics/RecordingImageBufferSurfaceTest.cpp:131: // for the
> current thread. The Mock thread is capable of queuing a single non-delyaed
task
> Nit: non-delayed

LGTM with the above fixed

[Justin Novosad, 2014-07-29 19:07:39]

The CQ bit was checked by junov@chromium.org

[commit-bot: I haz the power, 2014-07-29 19:08:18]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/junov@chromium.org/429643002/20001

[commit-bot: I haz the power, 2014-07-29 20:46:41]

Change committed as 179175