Revert of Revert of [Android] Support unfocusable container views.

Revert of Revert of [Android] Support unfocusable container views. (patchset #1 id:1 of https://codereview.chromium.org/712433002/)

Reason for revert:
Did not fix flake.

Original issue's description:
> Revert of [Android] Support unfocusable container views. (patchset #4 id:60001 of https://codereview.chromium.org/701233002/)
>
> Reason for revert:
> Introduced flake into WebRTCBrowserTest.* http://build.chromium.org/p/chromium.linux/buildstatus?builder=Android%20Tests%20%28dbg%29&number=23952
>
> Example:
> Value of: ExecuteScriptAndExtractString(shell()->web_contents(), javascript, &result)
>   Actual: false
> Expected: true
> From javascript: ../../content/test/webrtc_content_browsertest_base.cc:71: Failure
> Failed
> [INFO:CONSOLE(883)] "Receiving remote stream...", source: http://127.0.0.1:50076/media/peerconnection-call.html (883)
> [INFO:CONSOLE(859)] "Receiving answer...", source: http://127.0.0.1:50076/media/peerconnection-call.html (859)
> [  FAILED  ] WebRtcBrowserTest.AddTwoMediaStreamsToOnePC, where TypeParam =  and GetParam() =  (2180 ms)
>
> Original issue's description:
> > [Android] Support unfocusable container views.
> >
> > If the ContentViewCore container view is not focusable (which can
> > happen when it's emebedded in an app via android webview), we
> > were clearing the RWHVA notion of focus when the RenderView was
> > swapped out. As the view is never focusable again, chromium never
> > considers this view focused and as such, text selection did not
> > function.
> >
> > We support this type of container view by always treating it focused
> > from Chromium's point of view.
> >
> > BUG=430859
(internal b/18066784)
> >
> > Committed: https://crrev.com/9074d9fc9119ef4d2223f6c993d1a1b67a0bea7c
> > Cr-Commit-Position: refs/heads/master@{#303071}
>
> TBR=jdduke@chromium.org,benm@chromium.org
> NOTREECHECKS=true
> NOTRY=true
> BUG=430859
(internal b/18066784)
>
> Committed: https://crrev.com/1906fd177547e131f1320346df164a5dfd2122e4
> Cr-Commit-Position: refs/heads/master@{#303104}

TBR=jdduke@chromium.org,benm@chromium.org
NOTREECHECKS=true
NOTRY=true
BUG=430859
(internal b/18066784)

Committed: https://crrev.com/42aa48819ba501bca236a5951570b0571c2242e3
Cr-Commit-Position: refs/heads/master@{#303112}

[Nicolas Zea, 2014-11-06 22:56:15]

Created Revert of Revert of [Android] Support unfocusable container views.

[commit-bot: I haz the power, 2014-11-06 22:57:53]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/707043002/1

[commit-bot: I haz the power, 2014-11-06 22:59:55]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2014-11-06 23:01:27]

Patchset 1 (id:??) landed as
https://crrev.com/42aa48819ba501bca236a5951570b0571c2242e3
Cr-Commit-Position: refs/heads/master@{#303112}