Treat zero-width collapsed borders as invisible

Treat zero-width collapsed borders as invisible

We have fast-path for invisible collapsed borders. Treating zero-
width as invisible can improve performance in the case.

Also move core/style/CollapsedBorderValue.h to core/layout because
the structure is not used by any style code.

This CL will reduce frame time of PerformanceTests/Mutation/background-change-with-zero-width-collapsed-borders.html (in
https://codereview.chromium.org/2842313002/) by about 50%.

Review-Url: https://codereview.chromium.org/2842323002
Cr-Commit-Position: refs/heads/master@{#467741}
Committed: https://chromium.googlesource.com/chromium/src/+/4a9e4e47495a1c039b1948309bb45bdb8a88f6b5

[Xianzhu, 2017-04-26 22:00:29]

Description was changed from

==========
Treat zero-width collapsed borders as invisible

We have fast-path for invisible collapsed borders. Treating zero-
width as invisible can improve performance in the case.

Also move core/style/CollapsedBorderValue.h to core/layout because
the structure is not used by any style code.
==========

to

==========
Treat zero-width collapsed borders as invisible

We have fast-path for invisible collapsed borders. Treating zero-
width as invisible can improve performance in the case.

Also move core/style/CollapsedBorderValue.h to core/layout because
the structure is not used by any style code.
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2
==========

[Xianzhu, 2017-04-26 22:02:06]

Description was changed from

==========
Treat zero-width collapsed borders as invisible

We have fast-path for invisible collapsed borders. Treating zero-
width as invisible can improve performance in the case.

Also move core/style/CollapsedBorderValue.h to core/layout because
the structure is not used by any style code.
==========

to

==========
Treat zero-width collapsed borders as invisible

We have fast-path for invisible collapsed borders. Treating zero-
width as invisible can improve performance in the case.

Also move core/style/CollapsedBorderValue.h to core/layout because
the structure is not used by any style code.

This CL will reduce frame time of
PerformanceTests/Mutation/background-change-with-zero-width-collapsed-borders.html
(in
https://codereview.chromium.org/2842313002/) by about 50%.
==========

[Xianzhu, 2017-04-26 22:02:16]

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

[pdr., 2017-04-26 22:19:23]

You had me at -50%

LGTM

[Xianzhu, 2017-04-27 15:40:32]

The CQ bit was checked by wangxianzhu@chromium.org

[commit-bot: I haz the power, 2017-04-27 15:41:10]

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, 2017-04-27 19:08:08]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1493307632749150, "parent_rev":
"e1fa8fc5972327ce78225c7de95153c63d3e3bb3", "commit_rev":
"4a9e4e47495a1c039b1948309bb45bdb8a88f6b5"}

[commit-bot: I haz the power, 2017-04-27 19:08:16]

Description was changed from

==========
Treat zero-width collapsed borders as invisible

We have fast-path for invisible collapsed borders. Treating zero-
width as invisible can improve performance in the case.

Also move core/style/CollapsedBorderValue.h to core/layout because
the structure is not used by any style code.

This CL will reduce frame time of
PerformanceTests/Mutation/background-change-with-zero-width-collapsed-borders.html
(in
https://codereview.chromium.org/2842313002/) by about 50%.
==========

to

==========
Treat zero-width collapsed borders as invisible

We have fast-path for invisible collapsed borders. Treating zero-
width as invisible can improve performance in the case.

Also move core/style/CollapsedBorderValue.h to core/layout because
the structure is not used by any style code.

This CL will reduce frame time of
PerformanceTests/Mutation/background-change-with-zero-width-collapsed-borders.html
(in
https://codereview.chromium.org/2842313002/) by about 50%.

Review-Url: https://codereview.chromium.org/2842323002
Cr-Commit-Position: refs/heads/master@{#467741}
Committed:
https://chromium.googlesource.com/chromium/src/+/4a9e4e47495a1c039b1948309bb4...
==========

[commit-bot: I haz the power, 2017-04-27 19:08:17]

Committed patchset #1 (id:1) as
https://chromium.googlesource.com/chromium/src/+/4a9e4e47495a1c039b1948309bb4...