Usage of ThreadTaskRunner in lieu of in [chrome/browser/sync],[components/sync_driver]

Replace MessageLoopProxy usage with ThreadTaskRunnerHandle in chrome/browser/sync module & corresponding dependencies in components/sync_driver module

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

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

MessageLoopProxy -> SingleThreadTaskRunner

BUG=391045
Committed: https://crrev.com/ac08132daccb3fa9ded31f89e037a9436d88d9b8
Cr-Commit-Position: refs/heads/master@{#328710}

[Pranay, 2015-05-05 09:51:23]

pranay.kumar@samsung.com changed reviewers:
+ blundell@chromium.org, sky@chromium.org

[Pranay, 2015-05-05 09:51:24]

blundell@chromium.org: Please review changes in [components] module

sky@chromium.org: Please review changes in [chrome/browser] module

[blundell, 2015-05-05 10:51:11]

blundell@chromium.org changed reviewers:
+ zea@chromium.org
- sky@chromium.org

[blundell, 2015-05-05 10:51:11]

-blundell, sky

zea@ is the best reviewer for this CL, since he is an OWNER of all of the sync
code.

[blundell, 2015-05-05 10:51:25]

blundell@chromium.org changed reviewers:
- blundell@chromium.org

[Nicolas Zea, 2015-05-06 00:09:06]

Mostly LG, but please forward declare base::SingleThreadTaskRunner when it's not
actually being used.

https://codereview.chromium.org/1128523002/diff/1/chrome/browser/sync/glue/fr...
File chrome/browser/sync/glue/frontend_data_type_controller.h (right):

https://codereview.chromium.org/1128523002/diff/1/chrome/browser/sync/glue/fr...
chrome/browser/sync/glue/frontend_data_type_controller.h:13: #include
"base/single_thread_task_runner.h"
Can you just forward declare this (here and elsewhere)?

[Pranay, 2015-05-06 03:47:33]

Done

https://codereview.chromium.org/1128523002/diff/1/chrome/browser/sync/glue/fr...
File chrome/browser/sync/glue/frontend_data_type_controller.h (right):

https://codereview.chromium.org/1128523002/diff/1/chrome/browser/sync/glue/fr...
chrome/browser/sync/glue/frontend_data_type_controller.h:13: #include
"base/single_thread_task_runner.h"
On 2015/05/06 00:09:06, Nicolas Zea wrote:
> Can you just forward declare this (here and elsewhere)?

Done.

[Pranay, 2015-05-06 03:47:46]

PTAL

[Nicolas Zea, 2015-05-06 23:13:59]

lgtm

[Pranay, 2015-05-07 02:41:05]

The CQ bit was checked by pranay.kumar@samsung.com

[commit-bot: I haz the power, 2015-05-07 02:42:23]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1128523002/20001

[commit-bot: I haz the power, 2015-05-07 04:56:55]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2015-05-07 04:58:02]

Patchset 2 (id:??) landed as
https://crrev.com/ac08132daccb3fa9ded31f89e037a9436d88d9b8
Cr-Commit-Position: refs/heads/master@{#328710}