[blink] Skip ancestor clip in PaintLayerPainter for squashed layers.

[blink] Skip ancestor clip in PaintLayerPainter for squashed layers.

The squashing layer passed a differrent painting root that is not the same
as the backing's space when painting squashed layers, thus a wrong clip
is applied when squashed layers are painted.

This was not a problem prior to GeometryMapper-based PaintLayerClipper
because the non-GM PaintLayerClipper skipped visual rect optimization
in this particular corner case.

BUG=712783
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2

Review-Url: https://codereview.chromium.org/2830013007
Cr-Commit-Position: refs/heads/master@{#467220}
Committed: https://chromium.googlesource.com/chromium/src/+/fb28c1b7511ceeb4d47ed42dbeb0676591469fe6

[trchen, 2017-04-21 23:45:55]

Description was changed from

==========
[blink] Skip ancestor clip in PaintLayerPainter for squashed layers.

The squashing layer passed a differrent painting root that is not the same
as the backing's space when painting squashed layers, thus a wrong clip
is applied when squashed layers are painted.

This was not a problem prior to GeometryMapper-based PaintLayerClipper
because the non-GM PaintLayerClipper skipped visual rect optimization
in this particular corner case.

BUG=712783
==========

to

==========
[blink] Skip ancestor clip in PaintLayerPainter for squashed layers.

The squashing layer passed a differrent painting root that is not the same
as the backing's space when painting squashed layers, thus a wrong clip
is applied when squashed layers are painted.

This was not a problem prior to GeometryMapper-based PaintLayerClipper
because the non-GM PaintLayerClipper skipped visual rect optimization
in this particular corner case.

BUG=712783
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2
==========

[trchen, 2017-04-21 23:46:40]

trchen@chromium.org changed reviewers:
+ chrishtr@chromium.org

[trchen, 2017-04-21 23:46:41]

An alternative to https://codereview.chromium.org/2828323003/

WDYT?

[chrishtr, 2017-04-23 17:13:44]

lgtm

This approach looks good to me - I like not making PLC more complicated.

https://codereview.chromium.org/2830013007/diff/1/third_party/WebKit/Source/c...
File third_party/WebKit/Source/core/paint/PaintLayerPainter.cpp (right):

https://codereview.chromium.org/2830013007/diff/1/third_party/WebKit/Source/c...
third_party/WebKit/Source/core/paint/PaintLayerPainter.cpp:762: // This
workaround a bug in squash layer painting.
Nit: "This works around a bug in squashed-layer painting"

[chrishtr, 2017-04-23 17:14:06]

Oh actually - not LGTM yet. Please add a test (layout test of this example is
fine).

[chrishtr, 2017-04-23 17:14:11]

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

[commit-bot: I haz the power, 2017-04-23 17:14:19]

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, 2017-04-23 18:44:59]

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

[commit-bot: I haz the power, 2017-04-23 18:45:00]

Dry run: This issue passed the CQ dry run.

[trchen, 2017-04-25 21:44:57]

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

[trchen, 2017-04-25 21:45:07]

Done. :)

[commit-bot: I haz the power, 2017-04-25 21:45:32]

Dry run: CQ is trying da patch.

Follow status at:
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[chrishtr, 2017-04-25 22:11:05]

lgtm

https://codereview.chromium.org/2830013007/diff/20001/third_party/WebKit/Sour...
File third_party/WebKit/Source/core/paint/PaintLayerPainter.cpp (right):

https://codereview.chromium.org/2830013007/diff/20001/third_party/WebKit/Sour...
third_party/WebKit/Source/core/paint/PaintLayerPainter.cpp:768: // This
workaround a bug in squash layer painting.
Nit: please change to "This works around a bug in squashed-layer painting"

[trchen, 2017-04-25 23:16:00]

https://codereview.chromium.org/2830013007/diff/20001/third_party/WebKit/Sour...
File third_party/WebKit/Source/core/paint/PaintLayerPainter.cpp (right):

https://codereview.chromium.org/2830013007/diff/20001/third_party/WebKit/Sour...
third_party/WebKit/Source/core/paint/PaintLayerPainter.cpp:768: // This
workaround a bug in squash layer painting.
On 2017/04/25 22:11:04, chrishtr wrote:
> Nit: please change to "This works around a bug in squashed-layer painting"

Done.

[trchen, 2017-04-25 23:16:04]

The CQ bit was checked by trchen@chromium.org

[trchen, 2017-04-25 23:16:04]

The patchset sent to the CQ was uploaded after l-g-t-m from
chrishtr@chromium.org
Link to the patchset: https://codereview.chromium.org/2830013007/#ps40001
(title: "aye aye sir")

[commit-bot: I haz the power, 2017-04-25 23:16:50]

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, 2017-04-26 03:09:13]

CQ is committing da patch.

Bot data: {"patchset_id": 40001, "attempt_start_ts": 1493162164413310,
"parent_rev": "cb56b4ff751b3fef6ada2ae547a2c374caca8361", "commit_rev":
"fb28c1b7511ceeb4d47ed42dbeb0676591469fe6"}

[commit-bot: I haz the power, 2017-04-26 03:09:50]

Description was changed from

==========
[blink] Skip ancestor clip in PaintLayerPainter for squashed layers.

The squashing layer passed a differrent painting root that is not the same
as the backing's space when painting squashed layers, thus a wrong clip
is applied when squashed layers are painted.

This was not a problem prior to GeometryMapper-based PaintLayerClipper
because the non-GM PaintLayerClipper skipped visual rect optimization
in this particular corner case.

BUG=712783
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2
==========

to

==========
[blink] Skip ancestor clip in PaintLayerPainter for squashed layers.

The squashing layer passed a differrent painting root that is not the same
as the backing's space when painting squashed layers, thus a wrong clip
is applied when squashed layers are painted.

This was not a problem prior to GeometryMapper-based PaintLayerClipper
because the non-GM PaintLayerClipper skipped visual rect optimization
in this particular corner case.

BUG=712783
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2

Review-Url: https://codereview.chromium.org/2830013007
Cr-Commit-Position: refs/heads/master@{#467220}
Committed:
https://chromium.googlesource.com/chromium/src/+/fb28c1b7511ceeb4d47ed42dbeb0...
==========

[commit-bot: I haz the power, 2017-04-26 03:09:51]

Committed patchset #3 (id:40001) as
https://chromium.googlesource.com/chromium/src/+/fb28c1b7511ceeb4d47ed42dbeb0...