cros: Fix race on feedback extension loading

cros: Fix race on feedback extension loading

- Move ExtensionHost check before loading feedback extension to fix the
  race that ExtensionHost check could run after the loading makes
  feedback background page up and running;
- Handle the case where feedkback background host already exists,
  just in case.
- Add a retry in EnsureFeedbackUI to be sure the UI will be created;

BUG=711123
Review-Url: https://codereview.chromium.org/2837613002
Cr-Commit-Position: refs/heads/master@{#466395}
Committed: https://chromium.googlesource.com/chromium/src/+/24d15b15c85b8d3a60c6985add50824fa6602467

[xiyuan, 2017-04-21 16:19:46]

xiyuan@chromium.org changed reviewers:
+ warx@chromium.org

[xiyuan, 2017-04-21 17:25:28]

The CQ bit was checked by xiyuan@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2017-04-21 17:25:54]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[Qiang(Joe) Xu, 2017-04-21 17:47:12]

On 2017/04/21 16:19:47, xiyuan wrote:

LGTM

[commit-bot: I haz the power, 2017-04-21 17:59:58]

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

[commit-bot: I haz the power, 2017-04-21 17:59:59]

Dry run: This issue passed the CQ dry run.

[xiyuan, 2017-04-21 18:07:59]

The CQ bit was checked by xiyuan@chromium.org

[commit-bot: I haz the power, 2017-04-21 18:08:29]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2017-04-21 18:13:11]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1492798079723070, "parent_rev":
"3f80504b4bad121fb16e3e7dad008555baf44905", "commit_rev":
"24d15b15c85b8d3a60c6985add50824fa6602467"}

[commit-bot: I haz the power, 2017-04-21 18:13:20]

Description was changed from

==========
cros: Fix race on feedback extension loading

- Move ExtensionHost check before loading feedback extension to fix the
  race that ExtensionHost check could run after the loading makes
  feedback background page up and running;
- Handle the case where feedkback background host already exists,
  just in case.
- Add a retry in EnsureFeedbackUI to be sure the UI will be created;

BUG=711123
==========

to

==========
cros: Fix race on feedback extension loading

- Move ExtensionHost check before loading feedback extension to fix the
  race that ExtensionHost check could run after the loading makes
  feedback background page up and running;
- Handle the case where feedkback background host already exists,
  just in case.
- Add a retry in EnsureFeedbackUI to be sure the UI will be created;

BUG=711123

Review-Url: https://codereview.chromium.org/2837613002
Cr-Commit-Position: refs/heads/master@{#466395}
Committed:
https://chromium.googlesource.com/chromium/src/+/24d15b15c85b8d3a60c6985add50...
==========

[commit-bot: I haz the power, 2017-04-21 18:13:21]

Committed patchset #1 (id:1) as
https://chromium.googlesource.com/chromium/src/+/24d15b15c85b8d3a60c6985add50...