Use scoped_refptr<SingleThreadTaskRunner> when initializing ProxyConfigService

Use scoped_refptr<SingleThreadTaskRunner> when initializing ProxyConfigService

Previously MessageLoop was used to pass reference to the FILE thread
to ProxyConfigServiceLinux. Changeed it to use SingleThreadTaskRunner.
Also for other thread the task runners were passed as raw pointers.
Changed it to use scoped_refptr<> instead.

TBR=jochen@chromium.org

Committed: https://crrev.com/3f923064c11c69f13a7aba56dce6620a33166c94
Cr-Commit-Position: refs/heads/master@{#293395}

[Sergey Ulanov, 2014-09-03 22:33:03]

sergeyu@chromium.org changed reviewers:
+ mmenke@chromium.org

[mmenke, 2014-09-03 22:56:20]

I'll take a look tomorrow, but is there a reason not to use SequencedTaskRunner?

[Sergey Ulanov, 2014-09-03 23:19:23]

On 2014/09/03 22:56:20, mmenke wrote:
> I'll take a look tomorrow, but is there a reason not to use
SequencedTaskRunner?

Mac and Linux implementations depend on the thread being an IO and File threads
(i.e. MessageLoopForIO::current() != NULL). So these task runner will always
correspond to a specific thread.

[mmenke, 2014-09-04 16:14:35]

On 2014/09/03 23:19:23, Sergey Ulanov wrote:
> On 2014/09/03 22:56:20, mmenke wrote:
> > I'll take a look tomorrow, but is there a reason not to use
> SequencedTaskRunner?
> 
> Mac and Linux implementations depend on the thread being an IO and File
threads
> (i.e. MessageLoopForIO::current() != NULL). So these task runner will always
> correspond to a specific thread.

Ahh, I hadn't realized there were things you could do on a MessageLoopForIO, but
not a SequencedWorkerPool's task runner.  Makes sense, though, for watching for
events.

LGTM

[Sergey Ulanov, 2014-09-04 21:57:32]

The CQ bit was checked by sergeyu@chromium.org

[commit-bot: I haz the power, 2014-09-04 22:05:16]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/sergeyu@chromium.org/540593002/60001

[commit-bot: I haz the power, 2014-09-05 00:16:13]

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

[commit-bot: I haz the power, 2014-09-05 00:16:14]

Try jobs failed on following builders:
  chromium_presubmit on tryserver.chromium.linux
(http://build.chromium.org/p/tryserver.chromium.linux/builders/chromium_presub...)

[Sergey Ulanov, 2014-09-05 00:25:24]

sergeyu@chromium.org changed reviewers:
+ jochen@chromium.org

[Sergey Ulanov, 2014-09-05 00:25:57]

+jochen@ in TBR for no-op changes in src/content and src/chrome

[Sergey Ulanov, 2014-09-05 00:26:43]

The CQ bit was checked by sergeyu@chromium.org

[commit-bot: I haz the power, 2014-09-05 00:29:53]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/sergeyu@chromium.org/540593002/60001

[commit-bot: I haz the power, 2014-09-05 01:42:50]

Committed patchset #4 (id:60001) as a0b197593df55fb24e37d23fa78ee3a5cd57ed1f

[commit-bot: I haz the power, 2014-09-10 03:35:17]

Patchset 4 (id:??) landed as
https://crrev.com/3f923064c11c69f13a7aba56dce6620a33166c94
Cr-Commit-Position: refs/heads/master@{#293395}