[chrome/browser/media] Replace MessageLoopProxy usage with ThreadTaskRunnerHandle

Replace MessageLoopProxy usage with ThreadTaskRunnerHandle in chrome/browser/media module.

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

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

BUG=391045
Committed: https://crrev.com/68996efb6724bb848a58282faf2b0115367830bb
Cr-Commit-Position: refs/heads/master@{#327738}

[anujsharma, 2015-04-30 09:45:19]

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

[anujsharma, 2015-04-30 09:45:19]

PTAL

This is a very trivial change. Sending it module wise, so that it should make
the bots red.

Thanks!!

[xhwang, 2015-04-30 15:53:08]

lgtm

[anujsharma, 2015-04-30 16:21:10]

On 2015/04/30 15:53:08, xhwang wrote:
> lgtm

Thanks xhwang for lgtm.

[anujsharma, 2015-04-30 16:21:24]

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

[anujsharma, 2015-04-30 16:21:24]

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

[anujsharma, 2015-04-30 16:21:25]

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

[commit-bot: I haz the power, 2015-04-30 16:21:56]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1110333006/1

[commit-bot: I haz the power, 2015-04-30 17:59:52]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-04-30 18:00:47]

Patchset 1 (id:??) landed as
https://crrev.com/68996efb6724bb848a58282faf2b0115367830bb
Cr-Commit-Position: refs/heads/master@{#327738}