Revert of Revert of Add Mojo interfaces for out-of-process proxy resolver.

Revert of Revert of Add Mojo interfaces for out-of-process proxy resolver. (patchset #1 id:1 of https://codereview.chromium.org/892373006/)

Reason for revert:
The code in this change is not linked into any binary.

Test is flaky:
http://test-results.appspot.com/dashboards/flakiness_dashboard.html#testType=device_unittests&tests=SerialConnectionTest.Cancel

The likely cause of the test failure is https://chromium.googlesource.com/chromium/src/+/bc78a2320b50eba4fe397f1f838a82ad30b16cd6. The author has been informed and the test will be fixed soon.

Original issue's description:
> Revert of Add Mojo interfaces for out-of-process proxy resolver. (patchset #4 id:60001 of https://codereview.chromium.org/900433003/)
>
> Reason for revert:
> http://build.chromium.org/p/chromium.linux/builders/Linux%20Tests%20%28dbg%29%281%29/builds/38575
> Broke device_unittests device_unittests SerialConnectionTest.Cancel it seems.
>
> Original issue's description:
> > Add Mojo interfaces for out-of-process proxy resolver.
> >
> > See:
> > https://docs.google.com/a/chromium.org/document/d/1n5hr4KJhZl2A4MicTfmyiHPdiKp7kmUoWXnRBN8SrZE/edit#
> >
> > BUG=11746
> >
> > Committed: https://crrev.com/073e42bb7587b90594e5799fb6a4afe08a1e1561
> > Cr-Commit-Position: refs/heads/master@{#314509}
>
> TBR=rdsmith@chromium.org,eroman@chromium.org,sammc@chromium.org,amistry@chromium.org
> NOPRESUBMIT=true
> NOTREECHECKS=true
> NOTRY=true
> BUG=11746
>
> Committed: https://crrev.com/7d4ec1aa24e79406d29e0cafbb531a3fabfe815f
> Cr-Commit-Position: refs/heads/master@{#314519}

TBR=rdsmith@chromium.org,eroman@chromium.org,sammc@chromium.org,noel@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=11746
Committed: https://crrev.com/aa16ad225b47b9734e878bb4887651332fa12a9c
Cr-Commit-Position: refs/heads/master@{#314527}

[Anand Mistry (off Chromium), 2015-02-04 08:37:49]

Created Revert of Revert of Add Mojo interfaces for out-of-process proxy
resolver.

[Anand Mistry (off Chromium), 2015-02-04 08:38:35]

amistry@chromium.org changed reviewers:
- eroman@chromium.org, rdsmith@chromium.org, sammc@chromium.org

[Noel Gordon, 2015-02-04 09:00:47]

LGTM

[Noel Gordon, 2015-02-04 09:00:57]

The CQ bit was checked by noel@chromium.org

[commit-bot: I haz the power, 2015-02-04 09:01:21]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/882173005/1

[commit-bot: I haz the power, 2015-02-04 09:02:17]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-02-04 09:03:20]

Patchset 1 (id:??) landed as
https://crrev.com/aa16ad225b47b9734e878bb4887651332fa12a9c
Cr-Commit-Position: refs/heads/master@{#314527}

[eroman, 2015-02-05 19:09:13]

eroman@chromium.org changed reviewers:
+ eroman@chromium.org

[eroman, 2015-02-05 19:09:14]

lgtm