Enable writing layout tests for persistent notifications.

Enable writing layout tests for persistent notifications.

Layout tests written for persistent notifications will use the existing
infrastructure for page notifications. That means that they can be fully
interacted with using their regular, Web exposed API, but can also utilize
the existing permission plumbing and click simulation made available
through the TestRunner.

BUG=432527
Committed: https://crrev.com/fcd588f1804bd35550027bcc9e6e5dea4b42e5ee
Cr-Commit-Position: refs/heads/master@{#307782}

[Peter Beverloo, 2014-12-08 18:34:06]

peter@chromium.org changed reviewers:
+ mvanouwerkerk@chromium.org

[Peter Beverloo, 2014-12-08 18:34:06]

+mvanouwerkerk for initial review.

This depends on the following two CLs:
  https://codereview.chromium.org/776813004/
  https://codereview.chromium.org/728763003/

[Michael van Ouwerkerk, 2014-12-08 19:04:11]

lgtm

[Peter Beverloo, 2014-12-10 12:15:20]

peter@chromium.org changed reviewers:
+ mkwst@chromium.org

[Peter Beverloo, 2014-12-10 12:15:21]

+mkwst

[Peter Beverloo, 2014-12-10 19:34:49]

peter@chromium.org changed reviewers:
+ avi@chromium.org

[Peter Beverloo, 2014-12-10 19:34:50]

+avi, asking for your stamp since Mike is out sick.

This is plumbing for these two patches, which add the tests:
  https://codereview.chromium.org/787893002/
  https://codereview.chromium.org/789643003/

[Avi (use Gerrit), 2014-12-10 19:37:00]

stampity stamp LGTM

[Peter Beverloo, 2014-12-10 19:37:35]

The CQ bit was checked by peter@chromium.org

[commit-bot: I haz the power, 2014-12-10 19:38:36]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/789523002/40001

[commit-bot: I haz the power, 2014-12-10 19:51:31]

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

[commit-bot: I haz the power, 2014-12-10 19:51:32]

Try jobs failed on following builders:
  linux_chromium_compile_dbg_32_ng on tryserver.chromium.linux
(http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...)

[Peter Beverloo, 2014-12-10 19:54:56]

On 2014/12/10 19:51:32, I haz the power (commit-bot) wrote:
> Try jobs failed on following builders:
>   linux_chromium_compile_dbg_32_ng on tryserver.chromium.linux
>
(http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...)

That's crbug.com/440895.. trying again.

[Peter Beverloo, 2014-12-10 19:54:59]

The CQ bit was checked by peter@chromium.org

[commit-bot: I haz the power, 2014-12-10 19:56:03]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/789523002/40001

[commit-bot: I haz the power, 2014-12-10 22:42:27]

Committed patchset #3 (id:40001)

[commit-bot: I haz the power, 2014-12-10 22:43:18]

Patchset 3 (id:??) landed as
https://crrev.com/fcd588f1804bd35550027bcc9e6e5dea4b42e5ee
Cr-Commit-Position: refs/heads/master@{#307782}