wpt

8f5d77a1 - [carousel] Implement new focus behaviour for scroll-marker-group: links

[carousel] Implement new focus behaviour for scroll-marker-group: links When scroll-marker-group property of a scroller is set to `links`: 1) All ::scroll-marker pseudo-elements are tab stops, in order. 2) Activating a ::scroll-marker pseudo-element scrolls its originating element into view and sets the sequential focus navigation starting point to the originating element losing focus from the ::scroll-marker. Note that since the property is shipped and now we change its behaviour, there are unit tests with a new feature flag disabled to verify that we don't change the old behaviour. New tentative WPT tests are added to test new behaviours as well. The `tabs` mode will be implemented in the following CL. Bug: 425931511 Change-Id: I8d5a78a372881aead4af4223a91607a32f4838c9 Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6765563 Reviewed-by: Rune Lillesveen <futhark@chromium.org> Commit-Queue: Daniil Sakhapov <sakhapov@chromium.org> Cr-Commit-Position: refs/heads/main@{#1491962}