Add tests for closing a frame within the scope of a getusermedia callback.

content/test/data/media/webrtc_test_utilities.js

Index: content/test/data/media/webrtc_test_utilities.js
diff --git a/content/test/data/media/webrtc_test_utilities.js b/content/test/data/media/webrtc_test_utilities.js
index 5fd38113882b7c6bf7f9db219850291da9e4d2c6..9b93e4e52f5ee7e037af2c0e489c356d4ec2bdd2 100644
--- a/content/test/data/media/webrtc_test_utilities.js
+++ b/content/test/data/media/webrtc_test_utilities.js
@@ -26,7 +26,14 @@ function setAllEventsOccuredHandler(handler) {
 
 // Tells the C++ code we succeeded, which will generally exit the test.
 function reportTestSuccess() {
-  window.domAutomationController.send('OK');
+// If a test is reported to succeed and later a crash occurs

[phoglund_chromium, 2015/04/10 09:47:58]

Well, it's not "in the scope of the timer", it's rather we enqueue a new
javascript task after the current task completes. What about phrasing it like
this:

This function enqueues sending an OK back to the test, rather than doing it
directly. We do this so we catch crashes that occur in the current execution
context, but after reportTestSuccess is invoked.

[perkj_chrome, 2015/04/10 09:57:29]

Done.

+// after the reporting JavaScript has completed, the test will pass.
+// By completing the test in the scope of a timer, the reporting
+// JavaScript will finish and if that leads to a crash, it happens
+// before the test is reported to pass.
+  setTimeout(function () {
+    window.domAutomationController.send('OK');
+  }, 0);
 }
 
 // Returns a custom return value to the test.
@@ -228,4 +235,4 @@ function hasVideoInputDeviceOnSystem() {
     else
       sendValueToTest('no-video-input-devices');
   });
-}
+}