Revert of Remote Assistance on Chrome OS Part I - Aura Desktop Capturer

Revert of Remote Assistance on Chrome OS Part I - Aura Desktop Capturer (patchset #11 id:220001 of https://codereview.chromium.org/543243003/)

Reason for revert:
This patch appears to cause a Chrome OS bot to break.

http://build.chromium.org/p/chromium.chrome/buildstatus?builder=Google%20Chrome%20ChromeOS&number=71945

Original issue's description:
> Remote Assistance on Chrome OS - Aura Desktop Capturer
>
> This CL implements a WebRTC Desktop Capturer that captures from
> the Aura Shell root window.
>
> The capturer is used by the It2MeHost on Chrome OS.
> |DesktopCaptureDeviceAura| cannot be re-used in our scenario
> because is timer-driven as opposed to caller driven, which is
> required by WebRTC.
>
> The current implementation uses the layer API
>
> desktop_window_->layer()->RequestCopyOfOutput(request.Pass())
>
> to request the layer and its subtree to be rendered to a
> |SkiaBitmap|.  It then copies the pixels to a WebRTC |DesktopFrame|.
>
> BUG=411530
>
> Committed: https://crrev.com/278b065b519617b1e9231bd53e6502706d20787c
> Cr-Commit-Position: refs/heads/master@{#295187}

TBR=sergeyu@chromium.org,dcaiafa@chromium.org,darin@chromium.org,wez@chromium.org,jamescook@chromium.org,reed@google.com,danakj@chromium.org,sky@chromium.org,kelvinp@chromium.org
NOTREECHECKS=true
NOTRY=true
BUG=411530
Committed: https://crrev.com/365c61ee0448affac494e59101d58c286a3812f2
Cr-Commit-Position: refs/heads/master@{#295196}

[acolwell GONE FROM CHROMIUM, 2014-09-17 00:43:53]

Created Revert of Remote Assistance on Chrome OS Part I - Aura Desktop Capturer

[commit-bot: I haz the power, 2014-09-17 00:46:35]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patchset/579583003/1

[commit-bot: I haz the power, 2014-09-17 00:52:42]

Committed patchset #1 (id:1) as eeb5d064c46ddf84f02d819985d12bcadfec8461

[commit-bot: I haz the power, 2014-09-17 00:53:16]

Patchset 1 (id:??) landed as
https://crrev.com/365c61ee0448affac494e59101d58c286a3812f2
Cr-Commit-Position: refs/heads/master@{#295196}