Attempt to fix flaky PlatformAppBrowserTest.Messaging.

Attempt to fix flaky PlatformAppBrowserTest.Messaging.

This was re-enabled recently but was still flaky. This CL removes
another possible cause of flakiness and re-enables the test again.

BUG=171450
Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=287738

[Matt Giuca, 2014-08-06 05:19:54]

Can you explain in the CL description what it is that caused the flakiness (it
isn't entirely clear from reading the diff + the bug + the code).

Assuming you mean that you want to make sure the listeners in app2 are added
before attempting to launch app1. Therefore I have suggested a comment to
explain this in the code; if so then lgtm.

[Matt Giuca, 2014-08-06 05:20:03]

Oops, the comment.

https://codereview.chromium.org/448473003/diff/1/chrome/test/data/extensions/...
File chrome/test/data/extensions/platform_apps/messaging/app2/background.js
(right):

https://codereview.chromium.org/448473003/diff/1/chrome/test/data/extensions/...
chrome/test/data/extensions/platform_apps/messaging/app2/background.js:25:
chrome.test.sendMessage('Ready');
// Must ensure that the listeners are active before sending the "Ready" signal
(which will cause app1 to be launched).

[benwells, 2014-08-06 05:41:39]

https://codereview.chromium.org/448473003/diff/1/chrome/test/data/extensions/...
File chrome/test/data/extensions/platform_apps/messaging/app2/background.js
(right):

https://codereview.chromium.org/448473003/diff/1/chrome/test/data/extensions/...
chrome/test/data/extensions/platform_apps/messaging/app2/background.js:25:
chrome.test.sendMessage('Ready');
On 2014/08/06 05:20:03, Matt Giuca wrote:
> // Must ensure that the listeners are active before sending the "Ready" signal
> (which will cause app1 to be launched).

Done.

[benwells, 2014-08-06 05:41:49]

The CQ bit was checked by benwells@chromium.org

[commit-bot: I haz the power, 2014-08-06 05:43:19]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/benwells@chromium.org/448473003/20001

[commit-bot: I haz the power, 2014-08-06 09:07:20]

Change committed as 287738