1958779 - [wpt-sync] Sync PR 51873 - Add overflow default property for replaced element

Status: NEW

(Core :: CSS Parsing and Computation, task, P4)

Description

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

Sync web-platform-tests PR 51873 into mozilla-central (this bug is closed when the sync is complete).

PR: https://github.com/web-platform-tests/wpt/pull/51873
Details from upstream follow.

Kenzie Raditya Tirtarahardja <[e-mail]> wrote:

Add overflow default property for replaced element

Set default value for overflow attribute to replaced element. This is based on https://drafts.csswg.org/css-overflow-4/#overflow-control

We already implement the first half of the above spec previously.

Note that in chromium, author can change the overflow value of img and video, but not for iframe and embed. In Firefox, you cannot change the value for all above element.
https://jsfiddle.net/7m98gqsk/

There is also a possibility of handling this attribute somewhere in the rust code so that we do not have to change the UA stylesheet for every new replaced element. But for now, I just change the UA stylesheet just like mentioned in the spec.

Testing: this change does not change any result of the current test.
Fixes: #<!-- nolink -->35950

Try: https://github.com/PotatoCP/servo/actions/runs/14233254698

cc: @xiaochengh @d-desiatkin

Reviewed in servo/servo#36303