Don't pixel-snap overflow clips in clip paint property nodes.

Don't pixel-snap overflow clips in clip paint property nodes.

Pixel-snapping should be applied at "paint" time instead, based on context
which includes subpixel accumulation.

Also, adds code to apply subpixel accumulation for overflow clip rects applied
to background clip rects.

BUG=691959
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2

Review-Url: https://codereview.chromium.org/2701523003
Cr-Commit-Position: refs/heads/master@{#451189}
Committed: https://chromium.googlesource.com/chromium/src/+/19b6d116165378bc06ae204d74b5b1da58caa9ab

[chrishtr, 2017-02-16 00:50:40]

Description was changed from

==========
none


none


none

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

to

==========
none


none


none

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

[chrishtr, 2017-02-16 00:51:34]

Description was changed from

==========
none


none


none

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

to

==========
Don't pixel-snap overflow clips in clip paint property nodes.

Pixel-snapping should be applied at "paint" time instead, based on context
which includes subpixel accumulation.

BUG=691959
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2
==========

[chrishtr, 2017-02-16 00:51:56]

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

[commit-bot: I haz the power, 2017-02-16 00:52:51]

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, 2017-02-16 02:06:31]

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

[commit-bot: I haz the power, 2017-02-16 02:06:32]

Dry run: Try jobs failed on following builders:
  win_chromium_x64_rel_ng on master.tryserver.chromium.win (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.win/builders/win_chromium_x64_...)

[chrishtr, 2017-02-16 17:57:26]

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

[commit-bot: I haz the power, 2017-02-16 17:58:00]

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, 2017-02-16 20:00:00]

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

[commit-bot: I haz the power, 2017-02-16 20:00:01]

Dry run: Try jobs failed on following builders:
  mac_chromium_rel_ng on master.tryserver.chromium.mac (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.mac/builders/mac_chromium_rel_...)

[chrishtr, 2017-02-16 21:42:19]

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

[commit-bot: I haz the power, 2017-02-16 21:44:02]

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

[chrishtr, 2017-02-16 21:44:26]

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

[chrishtr, 2017-02-16 21:44:28]

https://codereview.chromium.org/2701523003/diff/60001/third_party/WebKit/Sour...
File third_party/WebKit/Source/core/paint/PaintLayerClipper.cpp (left):

https://codereview.chromium.org/2701523003/diff/60001/third_party/WebKit/Sour...
third_party/WebKit/Source/core/paint/PaintLayerClipper.cpp:295:
context.subPixelAccumulation);  // TODO(chrishtr): is this needed?
Confirmed that it is needed.

https://codereview.chromium.org/2701523003/diff/60001/third_party/WebKit/Sour...
File third_party/WebKit/Source/core/paint/PaintLayerClipper.cpp (right):

https://codereview.chromium.org/2701523003/diff/60001/third_party/WebKit/Sour...
third_party/WebKit/Source/core/paint/PaintLayerClipper.cpp:252: do {            
                                                     \
I adjusted this to not assert, in order to get better debugging output.
Regardless, the checks are not on in debug or any other compile mode
by default.

https://codereview.chromium.org/2701523003/diff/60001/third_party/WebKit/Sour...
third_party/WebKit/Source/core/paint/PaintLayerClipper.cpp:283:
rectToMap.move(context.subPixelAccumulation);
This is exercised by the layout test
fast/sub-pixel/fractional-border-location-and-size.html in addition to the
new unittest.

https://codereview.chromium.org/2701523003/diff/60001/third_party/WebKit/Sour...
third_party/WebKit/Source/core/paint/PaintLayerClipper.cpp:308:
foregroundRect.move(context.subPixelAccumulation);
I moved this above new line 309 for consistency with the old code.

[chrishtr, 2017-02-16 21:45:18]

Description was changed from

==========
Don't pixel-snap overflow clips in clip paint property nodes.

Pixel-snapping should be applied at "paint" time instead, based on context
which includes subpixel accumulation.

BUG=691959
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2
==========

to

==========
Don't pixel-snap overflow clips in clip paint property nodes.

Pixel-snapping should be applied at "paint" time instead, based on context
which includes subpixel accumulation.

Also, adds code to apply subpixel accumulation for overflow clip rects applied
to background clip rects.

BUG=691959
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2
==========

[Xianzhu, 2017-02-16 22:13:33]

lgtm

[chrishtr, 2017-02-16 23:25:35]

The CQ bit was checked by chrishtr@chromium.org

[chrishtr, 2017-02-16 23:25:36]

The patchset sent to the CQ was uploaded after l-g-t-m from
wangxianzhu@chromium.org
Link to the patchset: https://codereview.chromium.org/2701523003/#ps80001
(title: "Merge branch 'master' into fixclipping")

[commit-bot: I haz the power, 2017-02-16 23:26:01]

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, 2017-02-17 02:28:29]

CQ is committing da patch.

Bot data: {"patchset_id": 80001, "attempt_start_ts": 1487287535702270,
"parent_rev": "91503efd94b63d9be85603e7d1d6edf7e837f4c9", "commit_rev":
"19b6d116165378bc06ae204d74b5b1da58caa9ab"}

[commit-bot: I haz the power, 2017-02-17 02:29:15]

Description was changed from

==========
Don't pixel-snap overflow clips in clip paint property nodes.

Pixel-snapping should be applied at "paint" time instead, based on context
which includes subpixel accumulation.

Also, adds code to apply subpixel accumulation for overflow clip rects applied
to background clip rects.

BUG=691959
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2
==========

to

==========
Don't pixel-snap overflow clips in clip paint property nodes.

Pixel-snapping should be applied at "paint" time instead, based on context
which includes subpixel accumulation.

Also, adds code to apply subpixel accumulation for overflow clip rects applied
to background clip rects.

BUG=691959
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2

Review-Url: https://codereview.chromium.org/2701523003
Cr-Commit-Position: refs/heads/master@{#451189}
Committed:
https://chromium.googlesource.com/chromium/src/+/19b6d116165378bc06ae204d74b5...
==========

[commit-bot: I haz the power, 2017-02-17 02:29:16]

Committed patchset #5 (id:80001) as
https://chromium.googlesource.com/chromium/src/+/19b6d116165378bc06ae204d74b5...

[Matt Giuca, 2017-02-17 04:00:15]

A revert of this CL (patchset #5 id:80001) has been created in
https://codereview.chromium.org/2705493003/ by mgiuca@chromium.org.

The reason for reverting is: Failing layout test on Mac:
paint/invalidation/select-option-background-color.html

BUG=693345.

[Xianzhu, 2017-02-17 04:17:06]

On 2017/02/17 04:00:15, Matt Giuca wrote:
> A revert of this CL (patchset #5 id:80001) has been created in
> https://codereview.chromium.org/2705493003/ by mailto:mgiuca@chromium.org.
> 
> The reason for reverting is: Failing layout test on Mac:
> paint/invalidation/select-option-background-color.html
> 
> BUG=693345.

The revert has been closed in favor of
https://codereview.chromium.org/2694623015