Add runtime flag to enable the display list 2D canvas implementation

Add runtime flag to enable the display list 2D canvas implementation

This change adds the command line switch --enable-display-list-2d-canvas
and adds a corresponding entry to the chrome://flags page

BUG=392594
Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=285119

[Justin Novosad, 2014-07-21 21:29:06]

PTAL

[Justin Novosad, 2014-07-21 21:32:20]

On 2014/07/21 21:29:06, junov wrote:
> PTAL

Note: CL Depends on Blink r178585. Will start try jobs after DEPS roll.

[piman, 2014-07-21 21:45:56]

https://codereview.chromium.org/405163004/diff/1/content/child/runtime_featur...
File content/child/runtime_features.cc (right):

https://codereview.chromium.org/405163004/diff/1/content/child/runtime_featur...
content/child/runtime_features.cc:129: if
(command_line.HasSwitch(switches::kEnableDisplayList2dCanvas))
This will require you to forward the switch to the renderer (see
RenderProcessHostImpl::PropagateBrowserCommandLineToRenderer).

What is the relationship between the WebRuntimeFeatures flag and the
WebPreferences flag? e.g. if one is set but not the other one? If they need to
match, can we add a check?

[Justin Novosad, 2014-07-23 18:56:18]

New patch.

https://codereview.chromium.org/405163004/diff/1/content/child/runtime_featur...
File content/child/runtime_features.cc (right):

https://codereview.chromium.org/405163004/diff/1/content/child/runtime_featur...
content/child/runtime_features.cc:129: if
(command_line.HasSwitch(switches::kEnableDisplayList2dCanvas))
On 2014/07/21 21:45:56, piman (slow to review) wrote:
> This will require you to forward the switch to the renderer (see
> RenderProcessHostImpl::PropagateBrowserCommandLineToRenderer).
> 
> What is the relationship between the WebRuntimeFeatures flag and the
> WebPreferences flag? e.g. if one is set but not the other one? If they need to
> match, can we add a check?

Done.

[Justin Novosad, 2014-07-23 18:57:43]

More info: WebPreferences part was removed. It was a remnant of an earlier
version of this patch

[piman, 2014-07-23 19:14:01]

LGTM, thanks!

[Justin Novosad, 2014-07-23 19:16:22]

The CQ bit was checked by junov@chromium.org

[commit-bot: I haz the power, 2014-07-23 19:19:29]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/junov@chromium.org/405163004/20001

[commit-bot: I haz the power, 2014-07-24 02:34:48]

Change committed as 285119