Revert of Disable Mojo on RenderThreadImplBrowserTest on Android

Revert of Disable Mojo on RenderThreadImplBrowserTest on Android (patchset #1 id:1 of https://codereview.chromium.org/866973004/)

Reason for revert:
This doesn't work in some tests.

Original issue's description:
> Disable Mojo on RenderThreadImplBrowserTest on Android
>
> It hasn't worked from the beginning and it blocks ChannelMojo from
> being enabled.
>
> BUG=451221
> R=jcivelli@chromium.org, sky@chromium.org
>
> Committed: https://crrev.com/b5a99f2c1652471236c5d07403faa42bf53420df
> Cr-Commit-Position: refs/heads/master@{#312875}

TBR=jcivelli@chromium.org,sky@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=451221
Committed: https://crrev.com/2f16a8e145ce89fd744cfbb4be4eee235cfbc1c9
Cr-Commit-Position: refs/heads/master@{#312988}

[Hajime Morrita, 2015-01-24 01:31:53]

Created Revert of Disable Mojo on RenderThreadImplBrowserTest on Android

[commit-bot: I haz the power, 2015-01-24 01:33:17]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/873913002/1

[commit-bot: I haz the power, 2015-01-24 01:34:14]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-01-24 01:35:19]

Patchset 1 (id:??) landed as
https://crrev.com/2f16a8e145ce89fd744cfbb4be4eee235cfbc1c9
Cr-Commit-Position: refs/heads/master@{#312988}