Get rid of downcast>() in ScopedEventQueue::enqueueEvent(), for performance reasons.
Pull request: https://github.com/WebKit/WebKit/pull/25358
Committed 275576@main (81d1596b36a9): <https://commits.webkit.org/275576@main> Reviewed commits have been landed. Closing PR #25358 and removing active labels.
<rdar://problem/123924929>