Revert partially "cros: Use AlertDialog for remora device requisition."

Revert partially "cros: Use AlertDialog for remora device requisition."

This reverts the webui change from the commit 9cc0da7de2e00c403bb2672762009148e1846078 (https://codereview.chromium.org/61523002/).
The reverted webui change breaks alert dialogs in the Files app by making them not closable by pressing the Escape key.

TEST=Tested manually in Files app.
BUG=330835, 331739
Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=244064

[mtomasz, 2014-01-09 01:00:09]

@arv: PTAL. This is a manual partial revert, which we have to merge back to
M-33.

[xiyuan, 2014-01-09 03:05:32]

LGTM

[commit-bot: I haz the power, 2014-01-09 09:47:38]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/mtomasz@chromium.org/129973002/1

[commit-bot: I haz the power, 2014-01-09 12:41:53]

Retried try job too often on win_rel for step(s) browser_tests
http://build.chromium.org/p/tryserver.chromium/buildstatus?builder=win_rel&nu...

[arv (Not doing code reviews), 2014-01-09 15:28:08]

What is "remora device requisition"?

[arv (Not doing code reviews), 2014-01-09 15:28:31]

LGTM

[mtomasz, 2014-01-09 22:42:45]

On 2014/01/09 15:28:31, arv wrote:
> LGTM

@arv: I have no idea. @xiyuan should know.

[commit-bot: I haz the power, 2014-01-09 22:48:23]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/mtomasz@chromium.org/129973002/1

[commit-bot: I haz the power, 2014-01-10 03:06:59]

Change committed as 244064