Make ApplyStyleCommand::applyBlockStyle() to use connected position only

Make ApplyStyleCommand::applyBlockStyle() to use connected position only

This patch makes |ApplyStyleCommand::applyBlockStyle()| to use connected
position of |paragraphStart| by checking whether |paragraphStart| is connected
or not after calling |moveParagraphContentsToNewBlockIfNecessary()| which makes
anchor node of |paragraphStart| detached from document.

This patch also introduces |DCHECK(paragraphStart.isConnected()| to catch
other cases in future.

In crbug.com/626730, we call |endOfParagraph()| with disconnected position in
|paragraphStart| then we hit connected position |DCHECK| in |VisiblePosition|
constructor.

BUG=626730
TEST=LayoutTests/editing/execCommand/apply_style/justify_right_ul_br_crash.html

Committed: https://crrev.com/afbdbad679e6e40634a15ca8d91aaf0d46bcaec3
Cr-Commit-Position: refs/heads/master@{#407043}

[yosin_UTC9, 2016-07-21 07:13:14]

Description was changed from

==========
2016-07-21T16:09:41

BUG=
==========

to

==========
Abort ApplyStyleCommand::applyBlockStyle() when processing paragraph is removed


BUG=626730
TEST=LayoutTests/editing/execCommand/apply_style/justify_right_ul_br_crash.html
==========

[yosin_UTC9, 2016-07-21 07:13:22]

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

[commit-bot: I haz the power, 2016-07-21 07:13:36]

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

[yosin_UTC9, 2016-07-21 08:12:20]

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

[commit-bot: I haz the power, 2016-07-21 08:12:31]

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

[yosin_UTC9, 2016-07-21 08:20:21]

Description was changed from

==========
Abort ApplyStyleCommand::applyBlockStyle() when processing paragraph is removed


BUG=626730
TEST=LayoutTests/editing/execCommand/apply_style/justify_right_ul_br_crash.html
==========

to

==========
Make ApplyStyleCommand::applyBlockStyle() to use connected position only

This patch makes |ApplyStyleCommand::applyBlockStyle()| to use connected
position of |paragraphStart| by checking whether |paragraphStart| is connected
or not after calling |moveParagraphContentsToNewBlockIfNecessary()| which makes
anchor node of |paragraphStart| detached from document.

This patch also introduces |DCHECK(paragraphStart.isConnected()| to catch
other cases in future.

In crbug.com/626730, we call |endOfParagraph()| with disconnected position in
|paragraphStart| then we hit connected position |DCHECK| in |VisiblePosition|
constructor.

BUG=626730
TEST=LayoutTests/editing/execCommand/apply_style/justify_right_ul_br_crash.html
==========

[yosin_UTC9, 2016-07-21 08:45:22]

yosin@chromium.org changed reviewers:
+ yoichio@chromium.org

[yosin_UTC9, 2016-07-21 08:45:22]

PTAL

[commit-bot: I haz the power, 2016-07-21 12:13:46]

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

[commit-bot: I haz the power, 2016-07-21 12:13:47]

Dry run: Try jobs failed on following builders:
  linux_chromium_chromeos_rel_ng on master.tryserver.chromium.linux (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...)

[yoichio, 2016-07-22 02:04:43]

lgtm

[yosin_UTC9, 2016-07-22 02:13:00]

The CQ bit was checked by yosin@chromium.org

[commit-bot: I haz the power, 2016-07-22 02:13:53]

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, 2016-07-22 03:46:57]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2016-07-22 03:48:17]

Description was changed from

==========
Make ApplyStyleCommand::applyBlockStyle() to use connected position only

This patch makes |ApplyStyleCommand::applyBlockStyle()| to use connected
position of |paragraphStart| by checking whether |paragraphStart| is connected
or not after calling |moveParagraphContentsToNewBlockIfNecessary()| which makes
anchor node of |paragraphStart| detached from document.

This patch also introduces |DCHECK(paragraphStart.isConnected()| to catch
other cases in future.

In crbug.com/626730, we call |endOfParagraph()| with disconnected position in
|paragraphStart| then we hit connected position |DCHECK| in |VisiblePosition|
constructor.

BUG=626730
TEST=LayoutTests/editing/execCommand/apply_style/justify_right_ul_br_crash.html
==========

to

==========
Make ApplyStyleCommand::applyBlockStyle() to use connected position only

This patch makes |ApplyStyleCommand::applyBlockStyle()| to use connected
position of |paragraphStart| by checking whether |paragraphStart| is connected
or not after calling |moveParagraphContentsToNewBlockIfNecessary()| which makes
anchor node of |paragraphStart| detached from document.

This patch also introduces |DCHECK(paragraphStart.isConnected()| to catch
other cases in future.

In crbug.com/626730, we call |endOfParagraph()| with disconnected position in
|paragraphStart| then we hit connected position |DCHECK| in |VisiblePosition|
constructor.

BUG=626730
TEST=LayoutTests/editing/execCommand/apply_style/justify_right_ul_br_crash.html

Committed: https://crrev.com/afbdbad679e6e40634a15ca8d91aaf0d46bcaec3
Cr-Commit-Position: refs/heads/master@{#407043}
==========

[commit-bot: I haz the power, 2016-07-22 03:48:18]

Patchset 2 (id:??) landed as
https://crrev.com/afbdbad679e6e40634a15ca8d91aaf0d46bcaec3
Cr-Commit-Position: refs/heads/master@{#407043}