Introduce OpenURL to AppListControllerDelegate.

Introduce OpenURL to AppListControllerDelegate.

This does not change the current behavior, it simply opens a tab
by using chrome::Navigate().

However https://codereview.chromium.org/640103002/ will introduces
app-list search to Athena, then the direct use of chrome::Navigate()
is problematic. Athena will handle this method.

BUG=380875
R=xiyuan@chromium.org
TEST=no functional changes

Committed: https://crrev.com/b9a19ebab95668d4747e2161e779f027ee3da068
Cr-Commit-Position: refs/heads/master@{#299049}

[xiyuan, 2014-10-09 23:27:44]

lgtm

[Jun Mukai, 2014-10-10 00:16:14]

The CQ bit was checked by mukai@chromium.org

[commit-bot: I haz the power, 2014-10-10 00:17:46]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/644863002/1

[commit-bot: I haz the power, 2014-10-10 00:55:07]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2014-10-10 00:55:08]

Try jobs failed on following builders:
  linux_gpu on tryserver.chromium.gpu
(http://build.chromium.org/p/tryserver.chromium.gpu/builders/linux_gpu/builds/...)

[Jun Mukai, 2014-10-10 02:01:39]

The CQ bit was checked by mukai@chromium.org

[commit-bot: I haz the power, 2014-10-10 02:03:20]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/644863002/380001

[commit-bot: I haz the power, 2014-10-10 02:51:24]

Committed patchset #2 (id:380001)

[commit-bot: I haz the power, 2014-10-10 02:51:59]

Patchset 2 (id:??) landed as
https://crrev.com/b9a19ebab95668d4747e2161e779f027ee3da068
Cr-Commit-Position: refs/heads/master@{#299049}