Add test support for setting selected text option for <select> multiple

Add test support for setting selected text option for <select> multiple

The test framework returns an empty string as the localized strings are
not supported. This caused the assert to fail on android debug builds,
because of which https://codereview.chromium.org/541693003/ had to be
reverted. This is the chromium side changes needed for the patch to be
restored.

BUG=401506
Committed: https://crrev.com/bbfffe3bea9695231681aed4d3d4d23d09ced5b6
Cr-Commit-Position: refs/heads/master@{#296648}

[spartha, 2014-09-23 13:52:39]

sudarshan.p@samsung.com changed reviewers:
+ keishi@chromium.org, tkent@chromium.org

[spartha, 2014-09-23 13:53:47]

sudarshan.p@samsung.com changed reviewers:
+ jochen@chromium.org

[spartha, 2014-09-23 13:54:30]

sudarshan.p@samsung.com changed reviewers:
+ darin@chromium.org

[spartha, 2014-09-23 13:55:22]

This change is needed to restore https://codereview.chromium.org/541693003/
PTAL...Thanks!

[tkent, 2014-09-23 22:43:16]

non-owner lgtm

[spartha, 2014-09-24 07:36:32]

On 2014/09/23 22:43:16, tkent (high review load) wrote:
> non-owner lgtm

@darin, @jochen could one of you please take a look. This is a small patch.
Thanks!

[jochen (gone - plz use gerrit), 2014-09-24 20:06:01]

lgtm

[spartha, 2014-09-25 04:07:14]

The CQ bit was checked by sudarshan.p@samsung.com

[commit-bot: I haz the power, 2014-09-25 04:08:19]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/593113003/1

[commit-bot: I haz the power, 2014-09-25 05:00:46]

Committed patchset #1 (id:1) as 3fe7f6c108d9a46e8f70a0999c5e752528ab9d81

[commit-bot: I haz the power, 2014-09-25 05:01:42]

Patchset 1 (id:??) landed as
https://crrev.com/bbfffe3bea9695231681aed4d3d4d23d09ced5b6
Cr-Commit-Position: refs/heads/master@{#296648}