Remove special :scope matching code in MatchForRelation
This special path causes :scope selectors to incorrectly match
':scope *' selectors in shadow roots, when it actually should
match nothing [1].
The provided test scope-pseudo-in-shadow.html is passing in Firefox
and Safari. The existing WPT scope-selector.html (all browsers currently
passing) cover querySelector[All] cases well for shadow roots, document,
and other DocumentFragments. There should be no behavior change there.
Fixed: 378698644
[1] w3c/csswg-drafts#11188
[2] w3c/csswg-drafts#7261
Change-Id: I1efbf999864a766ad5dfaee1fd67527309e38107
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6011808
Reviewed-by: Rune Lillesveen futhark@chromium.org
Commit-Queue: Anders Hartvoll Ruud andruud@chromium.org
Cr-Commit-Position: refs/heads/main@{#1382339}