Simplify MessagePort garbage collection logic and align with the specification: - https://html.spec.whatwg.org/multipage/web-messaging.html#ports-and-garbage-collection
Pull request: https://github.com/WebKit/WebKit/pull/6173
Committed 256452@main (69660ff46e15): <https://commits.webkit.org/256452@main> Reviewed commits have been landed. Closing PR #6173 and removing active labels.
<rdar://problem/102096796>