Make Reflector Use Main Thread MessageLoop when in SingleThread

Make Reflector Use Main Thread MessageLoop when in SingleThread

When in using single thread with browser compositor, make reflector use
main thread MessageLoop instead.

Test with forced SW mirrored display on both Linux-cros build and Pixel.
BUG=453732
Committed: https://crrev.com/0b88b2372f1ad82c12656a4b9a17098470e576a1
Cr-Commit-Position: refs/heads/master@{#314665}

[weiliangc, 2015-02-04 21:31:31]

weiliangc@chromium.org changed reviewers:
+ danakj@chromium.org

[danakj, 2015-02-04 21:35:48]

LGTM

[weiliangc, 2015-02-04 21:37:04]

The CQ bit was checked by weiliangc@chromium.org

[commit-bot: I haz the power, 2015-02-04 21:38:10]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/899073003/1

[commit-bot: I haz the power, 2015-02-04 22:44:41]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-02-04 22:46:30]

Patchset 1 (id:??) landed as
https://crrev.com/0b88b2372f1ad82c12656a4b9a17098470e576a1
Cr-Commit-Position: refs/heads/master@{#314665}

[dcheng, 2015-02-05 03:14:36]

A revert of this CL (patchset #1 id:1) has been created in
https://codereview.chromium.org/900133002/ by dcheng@chromium.org.

The reason for reverting is: Reason for revert:
Speculatively reverting to try to fix broken Mac 10.8 retina layout tests in
Blink:
compositing/iframes/iframe-composited-scrolling-hide-and-show.html
compositing/iframes/overlapped-iframe-iframe.html
svg/as-border-image/svg-as-border-image-2.html
and more..

[oshima, 2015-02-05 04:03:06]

On 2015/02/05 03:14:36, dcheng wrote:
> A revert of this CL (patchset #1 id:1) has been created in
> https://codereview.chromium.org/900133002/ by mailto:dcheng@chromium.org.
> 
> The reason for reverting is: Reason for revert:
> Speculatively reverting to try to fix broken Mac 10.8 retina layout tests in
> Blink:
> compositing/iframes/iframe-composited-scrolling-hide-and-show.html
> compositing/iframes/overlapped-iframe-iframe.html
> svg/as-border-image/svg-as-border-image-2.html
> and more..

This is used only on chromeos, so the issue is most likely somewhere else.