Remove ClearSelection() from Layout{BlockFlow,Inline}::WillbeDestroyed()

Remove ClearSelection() from Layout{BlockFlow,Inline}::WillbeDestroyed()

LayoutView::ClearSelection was originally introduced at 2004 to assure no 
 crash:
https://chromium.googlesource.com/chromium/src/+/10f7ac6ea6784e33161c7979e9a59c5e2cae14b5 

Even now that code doesn't make sense because we update LayoutSelection after 
layout in following sequence:
1. FrameView::PerformPostLayoutTasks() checks 
 LayoutSelection::SetHasPendingSelection()
2. PaintLayerCompositor::UpdateIfNeededRecursiveInternal() calls 
 LayoutSelection::Commit() and it updates layout selection.



BUG=708453
Review-Url: https://codereview.chromium.org/2811333003
Cr-Commit-Position: refs/heads/master@{#464352}
Committed: https://chromium.googlesource.com/chromium/src/+/230b4e0eb7f14d23c70bc4134b8a23a9ddccd5a8

[yoichio, 2017-04-13 05:42:55]

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

[commit-bot: I haz the power, 2017-04-13 05:43:13]

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, 2017-04-13 07:27:46]

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

[commit-bot: I haz the power, 2017-04-13 07:27:47]

Dry run: This issue passed the CQ dry run.

[yoichio, 2017-04-13 08:14:08]

Description was changed from

==========
remove willbedestroyed

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

to

==========
Remove ClearSelection() from Layout{BlockFlow,Inline}::Willbedestroyed()

LayoutView::ClearSelection was originally introduced at 2004 to assure no 
 crash:
https://chromium.googlesource.com/chromium/src/+/10f7ac6ea6784e33161c7979e9a5...


Even now that code doesn't make sense because we update LayoutSelection after 
layout in following sequence:
1. FrameView::PerformPostLayoutTasks() checks 
 LayoutSelection::SetHasPendingSelection()
2. PaintLayerCompositor::UpdateIfNeededRecursiveInternal() calls 
 LayoutSelection::Commit() and it updates layout selection.



BUG=708453
==========

[yoichio, 2017-04-13 08:14:08]

yoichio@chromium.org changed reviewers:
+ eae@chromium.org, kojih@chromium.org, yosin@chromium.org

[yosin_UTC9, 2017-04-13 09:02:49]

Description was changed from

==========
Remove ClearSelection() from Layout{BlockFlow,Inline}::Willbedestroyed()

LayoutView::ClearSelection was originally introduced at 2004 to assure no 
 crash:
https://chromium.googlesource.com/chromium/src/+/10f7ac6ea6784e33161c7979e9a5...


Even now that code doesn't make sense because we update LayoutSelection after 
layout in following sequence:
1. FrameView::PerformPostLayoutTasks() checks 
 LayoutSelection::SetHasPendingSelection()
2. PaintLayerCompositor::UpdateIfNeededRecursiveInternal() calls 
 LayoutSelection::Commit() and it updates layout selection.



BUG=708453
==========

to

==========
Remove ClearSelection() from Layout{BlockFlow,Inline}::WillbeDestroyed()

LayoutView::ClearSelection was originally introduced at 2004 to assure no 
 crash:
https://chromium.googlesource.com/chromium/src/+/10f7ac6ea6784e33161c7979e9a5...


Even now that code doesn't make sense because we update LayoutSelection after 
layout in following sequence:
1. FrameView::PerformPostLayoutTasks() checks 
 LayoutSelection::SetHasPendingSelection()
2. PaintLayerCompositor::UpdateIfNeededRecursiveInternal() calls 
 LayoutSelection::Commit() and it updates layout selection.



BUG=708453
==========

[eae, 2017-04-13 09:03:59]

OK, LGTM

[yosin_UTC9, 2017-04-13 09:04:28]

lgtm

Good reasoning.

[yoichio, 2017-04-13 09:05:30]

The CQ bit was checked by yoichio@chromium.org

[commit-bot: I haz the power, 2017-04-13 09:05:48]

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, 2017-04-13 09:09:43]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1492074330446110, "parent_rev":
"9f5ce2d4fb3d35f5b2b22ad4f486d93b0d1acd50", "commit_rev":
"230b4e0eb7f14d23c70bc4134b8a23a9ddccd5a8"}

[commit-bot: I haz the power, 2017-04-13 09:10:28]

Description was changed from

==========
Remove ClearSelection() from Layout{BlockFlow,Inline}::WillbeDestroyed()

LayoutView::ClearSelection was originally introduced at 2004 to assure no 
 crash:
https://chromium.googlesource.com/chromium/src/+/10f7ac6ea6784e33161c7979e9a5...


Even now that code doesn't make sense because we update LayoutSelection after 
layout in following sequence:
1. FrameView::PerformPostLayoutTasks() checks 
 LayoutSelection::SetHasPendingSelection()
2. PaintLayerCompositor::UpdateIfNeededRecursiveInternal() calls 
 LayoutSelection::Commit() and it updates layout selection.



BUG=708453
==========

to

==========
Remove ClearSelection() from Layout{BlockFlow,Inline}::WillbeDestroyed()

LayoutView::ClearSelection was originally introduced at 2004 to assure no 
 crash:
https://chromium.googlesource.com/chromium/src/+/10f7ac6ea6784e33161c7979e9a5...


Even now that code doesn't make sense because we update LayoutSelection after 
layout in following sequence:
1. FrameView::PerformPostLayoutTasks() checks 
 LayoutSelection::SetHasPendingSelection()
2. PaintLayerCompositor::UpdateIfNeededRecursiveInternal() calls 
 LayoutSelection::Commit() and it updates layout selection.



BUG=708453

Review-Url: https://codereview.chromium.org/2811333003
Cr-Commit-Position: refs/heads/master@{#464352}
Committed:
https://chromium.googlesource.com/chromium/src/+/230b4e0eb7f14d23c70bc4134b8a...
==========

[commit-bot: I haz the power, 2017-04-13 09:10:29]

Committed patchset #1 (id:1) as
https://chromium.googlesource.com/chromium/src/+/230b4e0eb7f14d23c70bc4134b8a...

[yoichio, 2017-07-27 07:40:01]

A revert of this CL (patchset #1 id:1) has been created in
https://codereview.chromium.org/2988003002/ by yoichio@chromium.org.

The reason for reverting is: This causes use-after-free:
crbug.com/748718.