1939779 - [wpt-sync] Sync PR 49890 - Fix cull rect update for clipped scroller

Status: RESOLVED FIXED

(Core :: Layout: Scrolling and Overflow, task, P4)

Description

[Web Platform Test Sync Bot [:wpt-sync] (Matrix: #interop:mozilla.org)]

Sync web-platform-tests PR 49890 into mozilla-central (this bug is closed when the sync is complete).

PR: https://github.com/web-platform-tests/wpt/pull/49890
Details from upstream follow.

Xianzhu Wang <[e-mail]> wrote:

Fix cull rect update for clipped scroller

This fixes two causes of the bug:

1. We should proactively update cull rects of a scroller when its
   contents rect changes. In most cases, a change of contents rect
   will Set[Descendnat]NeedsRepaint of the scroller by the paint
   invalidator, but that's not the case if a containing-block-order
   descendant causing the change is not a paint-order descendant of
   the scroller.
2. When the input cull rect of a scroller is clipped by ancestors,
   the edge-touching logic in ChangedEnough is unreliable, so we need
   to skip the ChangedEnough check.

Actually, either of the above can avoid ChangedEnough and fix the bug,
but can potentially leave problems without the other, though I haven't
found a test case that can reproduce with only one of the above fixes.

Bug: 385704990
Change-Id: Ida6cb29483b0e51f6c9fcf2371c05b584e150fce

Reviewed-on: https://chromium-review.googlesource.com/6133753
WPT-Export-Revision: f5d56b87248acf01c1d51a3527e68a96a93dcd41

Comment 1

[Web Platform Test Sync Bot [:wpt-sync] (Matrix: #interop:mozilla.org)]

Pushed to try (stability) https://treeherder.mozilla.org/#/jobs?repo=try&revision=2d72385f806ee67065a0c8d62825c3351501c83a

Comment 2

[Web Platform Test Sync Bot [:wpt-sync] (Matrix: #interop:mozilla.org)]

CI Results

Ran 9 Firefox configurations based on mozilla-central, and Firefox, and Safari on GitHub CI

Total 2 tests

Status Summary

Firefox

PASS: 2

Safari

PASS: 2

Links

Gecko CI (Treeherder)
GitHub PR Head
GitHub PR Base

Comment 3

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/f5876a1c80eb
[wpt PR 49890] - Fix cull rect update for clipped scroller, a=testonly

Comment 4

[amarc]

https://hg.mozilla.org/mozilla-central/rev/f5876a1c80eb