Remove calls to deprecated MessageLoop methods in extensions.

Remove calls to deprecated MessageLoop methods in extensions.

This CL (hopefully) removes all calls to these methods in extensions:
- MessageLoop::PostTask
- MessageLoop::PostDelayedTask
- MessageLoop::DeleteSoon
- MessageLoop::ReleaseSoon
- MessageLoop::Run
- MessageLoop::RunUntilIdle

BUG=616447
R=reillyg@chromium.org

Committed: https://crrev.com/311b80864193429e1cb49bdf6e78014127bbf89a
Cr-Commit-Position: refs/heads/master@{#416758}

[fdoray, 2016-09-06 20:25:19]

The CQ bit was checked by fdoray@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2016-09-06 20:26:02]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-09-06 21:16:29]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2016-09-06 21:16:30]

Dry run: This issue passed the CQ dry run.

[fdoray, 2016-09-06 21:56:29]

PTAL

[Reilly Grant (use Gerrit), 2016-09-06 22:10:17]

lgtm

[fdoray, 2016-09-06 22:56:01]

The CQ bit was checked by fdoray@chromium.org

[commit-bot: I haz the power, 2016-09-06 22:56:53]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-09-06 23:13:19]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-09-06 23:17:23]

Description was changed from

==========
Remove calls to deprecated MessageLoop methods in extensions.

This CL (hopefully) removes all calls to these methods in extensions:
- MessageLoop::PostTask
- MessageLoop::PostDelayedTask
- MessageLoop::DeleteSoon
- MessageLoop::ReleaseSoon
- MessageLoop::Run
- MessageLoop::RunUntilIdle

BUG=616447
R=reillyg@chromium.org
==========

to

==========
Remove calls to deprecated MessageLoop methods in extensions.

This CL (hopefully) removes all calls to these methods in extensions:
- MessageLoop::PostTask
- MessageLoop::PostDelayedTask
- MessageLoop::DeleteSoon
- MessageLoop::ReleaseSoon
- MessageLoop::Run
- MessageLoop::RunUntilIdle

BUG=616447
R=reillyg@chromium.org

Committed: https://crrev.com/311b80864193429e1cb49bdf6e78014127bbf89a
Cr-Commit-Position: refs/heads/master@{#416758}
==========

[commit-bot: I haz the power, 2016-09-06 23:17:24]

Patchset 1 (id:??) landed as
https://crrev.com/311b80864193429e1cb49bdf6e78014127bbf89a
Cr-Commit-Position: refs/heads/master@{#416758}