Added GPU driver workaround for OSX multimonitor multisampling disabling

Added GPU driver workaround for OSX multimonitor multisampling disabling

BUG=280905
Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=220495

[bajones, 2013-08-29 06:19:00]

Please review. Thanks!

[Ken Russell (switch to Gerrit), 2013-08-29 19:28:00]

https://codereview.chromium.org/23473003/diff/3001/content/browser/gpu/gpu_da...
File content/browser/gpu/gpu_data_manager_impl_private.cc (right):

https://codereview.chromium.org/23473003/diff/3001/content/browser/gpu/gpu_da...
content/browser/gpu/gpu_data_manager_impl_private.cc:246: displayCount !=
manager->GetDisplayCount()) {
The workaround check needs to be done below in order to handle the situation
where a GPU switch event is fired for unrelated reasons. I think it would be
better to remove the check here, even though we'll be firing a GPU switch event
that has no effect.

https://codereview.chromium.org/23473003/diff/3001/content/browser/gpu/gpu_da...
content/browser/gpu/gpu_data_manager_impl_private.cc:827: || display_count_ > 1)
The check on the driver bug workaround should be done here:

  if (IsFeatureBlacklisted(gpu::GPU_FEATURE_TYPE_MULTISAMPLING) ||
      (display_count_ > 1 && manager->IsDriverBugWorkaroundActive(
          gpu::DISABLE_MULTIMONITOR_MULTISAMPLING))) {
    // ...
  }

[bajones, 2013-08-29 20:22:25]

On 2013/08/29 19:28:00, Ken Russell wrote:
> The check on the driver bug workaround should be done here...

"And that's why you don't post CLs at 11:00 at night."

Yes, you're absolutely right. :) Changed!

[Ken Russell (switch to Gerrit), 2013-08-29 21:05:04]

lgtm

https://codereview.chromium.org/23473003/diff/8001/content/browser/gpu/gpu_da...
File content/browser/gpu/gpu_data_manager_impl_private.cc (right):

https://codereview.chromium.org/23473003/diff/8001/content/browser/gpu/gpu_da...
content/browser/gpu/gpu_data_manager_impl_private.cc:244: if(displayCount !=
manager->GetDisplayCount()) {
Please undo this whitespace change.

[commit-bot: I haz the power, 2013-08-29 21:09:22]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/bajones@chromium.org/23473003/13001

[commit-bot: I haz the power, 2013-08-30 03:24:35]

Change committed as 220495