Revert of Support Compat mode inside of the desktop tree.

Revert of Support Compat mode inside of the desktop tree. (patchset #12 id:220001 of https://codereview.chromium.org/1191783002/)

Reason for revert:
Parent change reverted.
https://codereview.chromium.org/1185753008/

Original issue's description:
> Support Compat mode inside of the desktop tree.
>
> Depends on
> https://codereview.chromium.org/1185753008/
>
> Removes native bindings for Search+Shift+Arrows in favor of the extension commands bindings. Enables all ChromeVox Compat/Next commands inside of the desktop tree. Adds a test to exercise next element and next button commands.
>
> Also, whitelists root nodes without urls for ChromeVox compat. This includes the shelf/launcher.
>
> TEST=SpokenFeedbackTest.*
>
> Committed: https://crrev.com/e7b1c72c03dcf636e50917b2c8122e5d0ef884b6
> Cr-Commit-Position: refs/heads/master@{#336181}

TBR=dmazzoni@chromium.org,oshima@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

Committed: https://crrev.com/459d62d31a6ba4b24c6270428ba88f6d5e9393c8
Cr-Commit-Position: refs/heads/master@{#336195}

[David Tseng, 2015-06-25 17:49:46]

Created Revert of Support Compat mode inside of the desktop tree.

[commit-bot: I haz the power, 2015-06-25 17:51:59]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1213513003/1

[commit-bot: I haz the power, 2015-06-25 17:54:27]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-06-25 17:55:29]

Patchset 1 (id:??) landed as
https://crrev.com/459d62d31a6ba4b24c6270428ba88f6d5e9393c8
Cr-Commit-Position: refs/heads/master@{#336195}