Fix reentrancy crash in createWindowHelper

Fix reentrancy crash in createWindowHelper

BUG=619870
TEST=http/tests/loading/window-open-onblur-reentrancy.html

Committed: https://crrev.com/0a16bdd9b4f92ea68b2b40bfba075e8ba0a6fa83
Cr-Commit-Position: refs/heads/master@{#424482}

[Nate Chapin, 2016-10-04 23:24:47]

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

[commit-bot: I haz the power, 2016-10-04 23:25:10]

Dry run: 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, 2016-10-05 00:58:35]

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

[commit-bot: I haz the power, 2016-10-05 00:58:35]

Dry run: This issue passed the CQ dry run.

[Nate Chapin, 2016-10-05 17:28:31]

japhet@chromium.org changed reviewers:
+ dcheng@chromium.org

[Nate Chapin, 2016-10-05 17:29:31]

On 2016/10/05 17:28:32, Nate Chapin wrote:

It's not clear to me what the "right" behavior should be when a frame detach
while selecting an existing window for window.open(). I think failing is
probably better than creating a new window?

[dcheng, 2016-10-05 18:01:40]

Fun. LGTM

[Nate Chapin, 2016-10-11 16:39:47]

The CQ bit was checked by japhet@chromium.org

[commit-bot: I haz the power, 2016-10-11 16:39:58]

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, 2016-10-11 17:58:52]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-10-11 18:00:51]

Description was changed from

==========
Fix reentrancy crash in createWindowHelper

BUG=619870
TEST=http/tests/loading/window-open-onblur-reentrancy.html
==========

to

==========
Fix reentrancy crash in createWindowHelper

BUG=619870
TEST=http/tests/loading/window-open-onblur-reentrancy.html

Committed: https://crrev.com/0a16bdd9b4f92ea68b2b40bfba075e8ba0a6fa83
Cr-Commit-Position: refs/heads/master@{#424482}
==========

[commit-bot: I haz the power, 2016-10-11 18:00:52]

Patchset 1 (id:??) landed as
https://crrev.com/0a16bdd9b4f92ea68b2b40bfba075e8ba0a6fa83
Cr-Commit-Position: refs/heads/master@{#424482}