Validate execution context before printing CORS message

Validate execution context before printing CORS message

Need to check that context()->executionContext() is valid before we
try to print the CORS restriction message.

BUG=500929
TEST=none

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=197203

[Raymond Toy, 2015-06-16 16:07:19]

rtoy@chromium.org changed reviewers:
+ hongchan@chromium.org

[Raymond Toy, 2015-06-16 16:07:19]

PTAL.

[hongchan, 2015-06-16 16:12:10]

https://codereview.chromium.org/1189833003/diff/1/Source/modules/webaudio/Med...
File Source/modules/webaudio/MediaElementAudioSourceNode.cpp (right):

https://codereview.chromium.org/1189833003/diff/1/Source/modules/webaudio/Med...
Source/modules/webaudio/MediaElementAudioSourceNode.cpp:144: if
(context()->executionContext()) {
What happens if executionContext() does not exist? Is it even possible? (Perhaps
the context from a closed tab?)

[Raymond Toy, 2015-06-16 16:17:35]

On 2015/06/16 16:12:10, hoch wrote:
>
https://codereview.chromium.org/1189833003/diff/1/Source/modules/webaudio/Med...
> File Source/modules/webaudio/MediaElementAudioSourceNode.cpp (right):
> 
>
https://codereview.chromium.org/1189833003/diff/1/Source/modules/webaudio/Med...
> Source/modules/webaudio/MediaElementAudioSourceNode.cpp:144: if
> (context()->executionContext()) {
> What happens if executionContext() does not exist? Is it even possible?
(Perhaps
> the context from a closed tab?)

I think the document has gone away, usually by closing the tab.

[hongchan, 2015-06-16 16:25:48]

lgtm

[Raymond Toy, 2015-06-16 16:28:03]

The CQ bit was checked by rtoy@chromium.org

[commit-bot: I haz the power, 2015-06-16 16:28:21]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1189833003/1

[commit-bot: I haz the power, 2015-06-16 18:24:49]

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

[commit-bot: I haz the power, 2015-06-16 18:24:50]

Try jobs failed on following builders:
  win_blink_rel on tryserver.blink (JOB_FAILED,
http://build.chromium.org/p/tryserver.blink/builders/win_blink_rel/builds/66828)

[Raymond Toy, 2015-06-16 20:48:44]

The CQ bit was checked by rtoy@chromium.org

[commit-bot: I haz the power, 2015-06-16 20:49:18]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1189833003/1

[commit-bot: I haz the power, 2015-06-16 21:47:23]

Committed patchset #1 (id:1) as
https://src.chromium.org/viewvc/blink?view=rev&revision=197203