Sync web-platform-tests PR 28392 into mozilla-central (this bug is closed when the sync is complete).

PR: https://github.com/web-platform-tests/wpt/pull/28392
Details from upstream follow.

b'Rune Lillesveen <futhark@chromium.org>' wrote:

Call ChildrenRemoved() in base class first

Removed style recalc root has to be updated in
ContainerNode::ChildrenRemoved() before we can start marking style dirty
for the object/plugin. Otherwise the style traversal root code triggers
a DCHECK.

Bug: 1195633
Change-Id: I2e41a66ba869a23e1d3f246d3e1ba4d862709f3f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2807619
Reviewed-by: Mason Freed \<masonf@chromium.org>
Commit-Queue: Rune Lillesveen \<futhark@chromium.org>
Cr-Commit-Position: refs/heads/master@{#869908}

CI Results

Ran 14 Firefox configurations based on mozilla-central, and Firefox, Chrome, and Safari on GitHub CI

Total 1 tests

Status Summary

Firefox

PASS: 1

Chrome

PASS: 1

Safari

PASS: 1

Links

Gecko CI (Treeherder)
GitHub PR Head
GitHub PR Base

https://hg.mozilla.org/mozilla-central/rev/bb4928c53a5a