1943046 - [wpt-sync] Sync PR 50214 - Correctly cascade before-change style for @starting-style

Status: RESOLVED FIXED

(Core :: CSS Transitions and Animations, task, P4)

Description

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

Sync web-platform-tests PR 50214 into mozilla-central (this bug is closed when the sync is complete).

PR: https://github.com/web-platform-tests/wpt/pull/50214
Details from upstream follow.

Rune Lillesveen <[e-mail]> wrote:

Correctly cascade before-change style for @starting-style

Before-change style should inherit from parent after-change style for
@starting-style. That means we need to cascade after-change separately
also for before-change style in this case.

This CL separates out ensuring of after-change style so that it can be
shared between before- and after-change style computations.

Also, the StyleRecalcContext must be set up correctly with old_style to
ensure that:

1. @starting-style rules are not applied for after-change style.
2. @starting-style rules are applied for before-change style when
   @starting-style is the before-change for a given style resolution.

Bug: 40337057

Change-Id: I92af1934fbab45bb294ea92055ec3be373a8caa5
Reviewed-on: https://chromium-review.googlesource.com/6185041
WPT-Export-Revision: fa8f554fb9e13ad457b01b7ed1a80df871d76801

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=b8030fa1d5f654ad4debd81f97b68b8b7946e4a4

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 Chrome on GitHub CI

Total 1 tests and 5 subtests

Status Summary

Firefox

OK : 1
PASS: 5

Chrome

OK : 1
PASS: 4
FAIL: 1

Links

Gecko CI (Treeherder)
GitHub PR Head
GitHub PR Base

Comment 3

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/41ccd510e590
[wpt PR 50214] - Correctly cascade before-change style for @starting-style, a=testonly

Comment 4

[agoloman]

https://hg.mozilla.org/mozilla-central/rev/41ccd510e590