Use a HashSet instead of a std::unique_ptr<HashSet> for StyleRareNonInheritedData.customPaintWatchedProperties. A HashSet is already essentially a pointer, no need for the extra dereferencing.
Pull request: https://github.com/WebKit/WebKit/pull/428
Committed r293596 (250105@main): <https://commits.webkit.org/250105@main> Reviewed commits have been landed. Closing PR #428 and removing active labels.
<rdar://problem/92495615>