RemoteMediaResourceManager should keep track of PlatformMediaResource using ThreadSafeWeakPtr, not raw pointers.
Pull request: https://github.com/WebKit/WebKit/pull/16297
Committed 266600@main (bae62859f40c): <https://commits.webkit.org/266600@main> Reviewed commits have been landed. Closing PR #16297 and removing active labels.
<rdar://problem/113411062>