[rAC, OSX] Fix focus ring drawing.

[rAC, OSX] Fix focus ring drawing.

Ensure there is a) a focus ring around the entirety of the account
chooser, not just the image, if Chrome is running on 10.6. And b) use
the SDK's focus ring drawing from 10.7 on instead. (Before this CL,
10.7+ systems get _two_ focus rings for ImageButtonCells.)

BUG=308192
R=thakis@chromium.org

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=245293

[Nico, 2014-01-16 00:53:09]

lgtm, but I don't quite understand this (due to me not knowing how focus rings
work)

https://codereview.chromium.org/140353002/diff/1/chrome/browser/ui/cocoa/imag...
File chrome/browser/ui/cocoa/image_button_cell.mm (right):

https://codereview.chromium.org/140353002/diff/1/chrome/browser/ui/cocoa/imag...
chrome/browser/ui/cocoa/image_button_cell.mm:104: // Only draw custom focus ring
if the 10.7 focus ring APIs are not available.
Why? Who calls this on 10.7+?

[groby-ooo-7-16, 2014-01-16 01:05:50]

Focus rings used to be drawn by drawWithFrame:, which made invoking super's
drawWithFrame difficult. From 10.7 on, the focus ring gets a separate drawing
routine wherein you just draw the mask. NSButtonCell has a default
implementation that's invoked by these changes post 10.7, while preserving the
old-style rendering for 10.6. (Which is the current SDK we build against)

https://codereview.chromium.org/140353002/diff/1/chrome/browser/ui/cocoa/imag...
File chrome/browser/ui/cocoa/image_button_cell.mm (right):

https://codereview.chromium.org/140353002/diff/1/chrome/browser/ui/cocoa/imag...
chrome/browser/ui/cocoa/image_button_cell.mm:104: // Only draw custom focus ring
if the 10.7 focus ring APIs are not available.
On 2014/01/16 00:53:09, Nico wrote:
> Why? Who calls this on 10.7+?

10.7+ automatically draws a focus ring using drawFocusRingMaskWithFrame:inView:,
separate from the -drawWithFrame: invocation.

Quoting NSCell docs: "The Application Kit automatically invokes this method when
appropriate, to render the view's focus ring."

[commit-bot: I haz the power, 2014-01-16 01:30:14]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/groby@chromium.org/140353002/1

[commit-bot: I haz the power, 2014-01-16 02:33:30]

Retried try job too often on win_rel for step(s) base_unittests, browser_tests,
interactive_ui_tests, net_unittests, unit_tests
http://build.chromium.org/p/tryserver.chromium/buildstatus?builder=win_rel&nu...

[commit-bot: I haz the power, 2014-01-16 03:23:14]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/groby@chromium.org/140353002/300001

[commit-bot: I haz the power, 2014-01-16 19:52:34]

Change committed as 245293