Adding hasRecorded API method to SkDeferredCanvas

Adding hasPendingCommands API method to SkDeferredCanvas

BUG=http://code.google.com/p/chromium/issues/detail?id=146178
Committed: https://code.google.com/p/skia/source/detail?r=5632

[junov1, 2012-09-20 22:00:32]

PTAL

[Stephen White, 2012-09-20 22:02:56]

https://codereview.appspot.com/6550050/diff/1/include/utils/SkDeferredCanvas.h
File include/utils/SkDeferredCanvas.h (right):

https://codereview.appspot.com/6550050/diff/1/include/utils/SkDeferredCanvas....
include/utils/SkDeferredCanvas.h:93: bool hasRecorded() const;
bikeshed:  maybe hasRecordedCommands()?

[junov1, 2012-09-20 22:08:21]

Patch!

[Stephen White, 2012-09-20 22:09:20]

LGTM

[reed1, 2012-09-21 12:27:13]

Who is the caller of the new api?

[junov1, 2012-09-24 15:35:11]

Caller is WebKit, Canvas2DLayerBridge.cpp (CL in the works)
The method will be used to determine whether a block of JS code has added
pending commands to the canvas.  In conjunction with the isFreshFrame
method and the NotificationClient API, this will allow us to detect stale
canvases (canvases with two frames worth of deferral backlog).  This is so
we can replace the rate limiter (which does not work with the threaded
compositor) with a new mechanism that flushes deferred canvases when they
get stale.  This will effectively rate limit pages with canvases that do
not trigger the skip-on-clear optimization.  The end result is a quantum
leap in canvas animation smoothness, and it slightly improves frame rates
of non-RAF animations, with the threaded compositor enabled.

On Fri, Sep 21, 2012 at 8:27 AM, <reed@google.com> wrote:

> Who is the caller of the new api?
>
>
https://codereview.appspot.**com/6550050/<https://codereview.appspot.com/6550...
>