Resubmit: Add LocationBar PageAction tests

Resubmit: Add LocationBar PageAction tests

Original CL: https://codereview.chromium.org/512693003/

This was reverted because LocationBarBrowserTest.PageActionUITest is flaky on
Mac. Resubmit this, but with the flaky test disabled on mac.

BUG=408261
BUG=410866
Committed: https://crrev.com/65b063b53184d97bf17abeeeca8ff846bbe273cd
Cr-Commit-Position: refs/heads/master@{#293364}

[Devlin, 2014-09-04 15:54:20]

rdevlin.cronin@chromium.org changed reviewers:
+ sky@chromium.org

[Devlin, 2014-09-04 15:54:20]

Hey Scott, please take a look when you can.  It looks like the patch was
reverted because one of the tests was flaky on mac.  I'd like to resubmit with
the flaky test disabled on Mac so that
- Other platforms keep the test coverage (since it doesn't look like we had any
tests for this before).
- Re-enabling the flaky test is easier when it's fixed.
- We have a place to add more location bar tests as needed.

It does look like the test passes on every other platform:
http://chromium-build-logs.appspot.com/gtest_query?gtest_query=LocationBarBro...

[sky, 2014-09-04 17:51:01]

LGTM

[Devlin, 2014-09-04 19:15:40]

The CQ bit was checked by rdevlin.cronin@chromium.org

[commit-bot: I haz the power, 2014-09-04 19:18:26]

CQ is trying da patch. Follow status at

https://chromium-status.appspot.com/cq/rdevlin.cronin@chromium.org/543783002/...

[commit-bot: I haz the power, 2014-09-04 22:56:06]

Committed patchset #2 (id:20001) as 7714813d689e649c5087cfebb4138d5465b2e045

[commit-bot: I haz the power, 2014-09-10 03:33:34]

Patchset 2 (id:??) landed as
https://crrev.com/65b063b53184d97bf17abeeeca8ff846bbe273cd
Cr-Commit-Position: refs/heads/master@{#293364}