1872283 - [wpt-sync] Sync PR 43818 - In-effect animations should force a stacking context

Status: RESOLVED FIXED

(Core :: DOM: Animation, task, P4)

Description

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

Sync web-platform-tests PR 43818 into mozilla-central (this bug is closed when the sync is complete).

PR: https://github.com/web-platform-tests/wpt/pull/43818
Details from upstream follow.

David Bokan <[e-mail]> wrote:

In-effect animations should force a stacking context

An in-effect animation includes those that are in the before or after
phase with the animation having the corresponding fill. Per spec[1],
such animations should have a side-effect of being equivalent to having
will-change set to the target property.

https://crrev.com/46005e74c changed opacity animations to no longer have
clamp to a value below exactly 1. It turns out having a non-1 value was
what was causing opacity animations to force a stacking context; the
animation effect was only considered to be affecting a property if the
effect was current.

This CL updates the 'affecting' state to include animations that are in
effect.

[1] https://drafts.csswg.org/web-animations-1/#side-effects-section

Bug: 1511227
Change-Id: I05d7d274d004c55781e25734162eb3cc42ff36bb
Reviewed-on: https://chromium-review.googlesource.com/5155307
WPT-Export-Revision: 5f25a29d4d1d67e12d62d5c5b846ce83f771e705

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=53d3615f5e635c975ed91fed16bb0175437f92cb

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, Chrome, and Safari on GitHub CI

Total 3 tests

Status Summary

Firefox

PASS: 3

Chrome

PASS: 2
FAIL: 1

Safari

PASS: 3

Links

Gecko CI (Treeherder)
GitHub PR Head
GitHub PR Base

Comment 3

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/069d2992e899
[wpt PR 43818] - In-effect animations should force a stacking context, a=testonly

Comment 4

[Cristina Horotan [:chorotan]]

https://hg.mozilla.org/mozilla-central/rev/069d2992e899