Revert of Add test for ChromeVox keyboard commands.

Revert of Add test for ChromeVox keyboard commands. (patchset #6 of https://codereview.chromium.org/490443002/)

Reason for revert:
Broke interactive_ui_tests on chromium.chromiumos waterfall: http://build.chromium.org/p/chromium.chromiumos/builders/Linux%20ChromiumOS%20Ozone%20Tests%20%282%29/builds/1291

Original issue's description:
> Add test for ChromeVox keyboard commands.
> 
> This is just a couple of quick sanity checks to prevent future regressions
> like the one in the linked bug. It tests both a Search+Shift shortcut and
> the corresponding Prefix Key shortcut.
> 
> Adds support for sending the meta modifier key in
> aura/x11 tests.
> 
> BUG=404470
> 
> Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=291547

TBR=dtseng@chromium.org,sky@chromium.org,dmazzoni@chromium.org
NOTREECHECKS=true
NOTRY=true
BUG=404470
Committed: https://crrev.com/744746cc51ef81c8f8d727fafa46b14d1c03fe44
Cr-Commit-Position: refs/heads/master@{#291576}

[agable, 2014-08-23 20:49:36]

Created Revert of Add test for ChromeVox keyboard commands.

[commit-bot: I haz the power, 2014-08-23 20:50:13]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/agable@chromium.org/500833002/1

[commit-bot: I haz the power, 2014-08-23 20:51:22]

Committed patchset #1 (1) as 47c7b503ac17ae3038bffe0339d8a2a19f767693

[commit-bot: I haz the power, 2014-09-10 02:30:45]

Patchset 1 (id:??) landed as
https://crrev.com/744746cc51ef81c8f8d727fafa46b14d1c03fe44
Cr-Commit-Position: refs/heads/master@{#291576}