Fix crash in CSS.getLayoutTreeAndStyles

Fix crash in CSS.getLayoutTreeAndStyles

For pages where there was a FrameOwnerElement with a null
ContentDocument CSS.getLayoutTreeAndStyles would crash.  This patch
fixes that.

BUG=680497, 546953
Review-Url: https://codereview.chromium.org/2623273006
Cr-Commit-Position: refs/heads/master@{#443513}
Committed: https://chromium.googlesource.com/chromium/src/+/cc53e06971c8c55c85642a44fd350ebc092a5e8c

[alex clarke (OOO till 29th), 2017-01-12 17:16:19]

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

[alex clarke (OOO till 29th), 2017-01-12 17:16:43]

alexclarke@chromium.org changed reviewers:
+ dgozman@chromium.org, pfeldman@chromium.org

[alex clarke (OOO till 29th), 2017-01-12 17:16:44]

PTAL :)

[commit-bot: I haz the power, 2017-01-12 17:16:55]

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

[alex clarke (OOO till 29th), 2017-01-12 17:24:46]

Description was changed from

==========
Fix crash in CSS.getLayoutTreeAndStyles

For pages where there was a FrameOwnerElement with a null
ContentDocument CSS.getLayoutTreeAndStyles would crash.  This patch
fixes that.

BUG=680497
==========

to

==========
Fix crash in CSS.getLayoutTreeAndStyles

For pages where there was a FrameOwnerElement with a null
ContentDocument CSS.getLayoutTreeAndStyles would crash.  This patch
fixes that.

BUG=680497, 546953
==========

[commit-bot: I haz the power, 2017-01-12 18:48:58]

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

[commit-bot: I haz the power, 2017-01-12 18:48:59]

Dry run: This issue passed the CQ dry run.

[dgozman, 2017-01-12 21:31:48]

lgtm

[alex clarke (OOO till 29th), 2017-01-13 07:19:59]

The CQ bit was checked by alexclarke@chromium.org

[commit-bot: I haz the power, 2017-01-13 07:20:14]

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, 2017-01-13 07:23:59]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1484291999722440, "parent_rev":
"0ffd401266e9b6afb5e7595fcefd336765ffdc99", "commit_rev":
"cc53e06971c8c55c85642a44fd350ebc092a5e8c"}

[commit-bot: I haz the power, 2017-01-13 07:24:24]

Description was changed from

==========
Fix crash in CSS.getLayoutTreeAndStyles

For pages where there was a FrameOwnerElement with a null
ContentDocument CSS.getLayoutTreeAndStyles would crash.  This patch
fixes that.

BUG=680497, 546953
==========

to

==========
Fix crash in CSS.getLayoutTreeAndStyles

For pages where there was a FrameOwnerElement with a null
ContentDocument CSS.getLayoutTreeAndStyles would crash.  This patch
fixes that.

BUG=680497, 546953

Review-Url: https://codereview.chromium.org/2623273006
Cr-Commit-Position: refs/heads/master@{#443513}
Committed:
https://chromium.googlesource.com/chromium/src/+/cc53e06971c8c55c85642a44fd35...
==========

[commit-bot: I haz the power, 2017-01-13 07:24:25]

Committed patchset #1 (id:1) as
https://chromium.googlesource.com/chromium/src/+/cc53e06971c8c55c85642a44fd35...