Using ThreadTaskRunnerHandle in lieu of MessageLoopProxy in google_apis module

Using ThreadTaskRunnerHandle in lieu of MessageLoopProxy  in google_apis module

MessageLoopProxy is deprecated.
This basically does a search and replace of:

MessageLoopProxy::current() -> ThreadTaskRunnerHandle::Get().

MessageLoopProxy -> SingleThreadTaskRunner

BUG=391045
Committed: https://crrev.com/a898c5cf420b99d1014c639ca2271630b3369744
Cr-Commit-Position: refs/heads/master@{#329192}

[anujsharma, 2015-05-08 15:37:41]

anujk.sharma@samsung.com changed reviewers:
+ rogerta@chromium.org

[anujsharma, 2015-05-08 15:37:42]

PTAL

[Roger Tawa OOO till Jul 10th, 2015-05-11 16:58:49]

lgtm

[anujsharma, 2015-05-11 17:18:27]

On 2015/05/11 16:58:49, Roger Tawa wrote:
> lgtm

Thanks Roger Tawa for lgtm.

[anujsharma, 2015-05-11 17:18:59]

The CQ bit was checked by anujk.sharma@samsung.com

[commit-bot: I haz the power, 2015-05-11 17:25:41]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1135793002/1

[commit-bot: I haz the power, 2015-05-11 18:18:41]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-05-11 18:19:39]

Patchset 1 (id:??) landed as
https://crrev.com/a898c5cf420b99d1014c639ca2271630b3369744
Cr-Commit-Position: refs/heads/master@{#329192}