Switch to Ref<> and add assertions.
Created attachment 384047 [details] patch
Created attachment 384048 [details] patch
Created attachment 384052 [details] patch
Comment on attachment 384052 [details] patch Clearing flags on attachment: 384052 Committed r252742: <https://trac.webkit.org/changeset/252742>
All reviewed patches have been landed. Closing bug.
<rdar://problem/57401956>