enclosingClippingScopes() does an ancestor tree walk, and shows up in profiles on layer-heavy sites. It's called from both layerOverlaps() and addToOverlapMap(), so we can avoid one of those calls.
<rdar://problem/115734407>
Pull request: https://github.com/WebKit/WebKit/pull/17924
Committed 268176@main (6d84ae083179): <https://commits.webkit.org/268176@main> Reviewed commits have been landed. Closing PR #17924 and removing active labels.