Drop assertions landed in r244971 to debug rdar://problem/49877867. This radar has since been fixed.
<rdar://problem/101756784>
Pull request: https://github.com/WebKit/WebKit/pull/5954
Committed 256194@main (b802e43b203c): <https://commits.webkit.org/256194@main> Reviewed commits have been landed. Closing PR #5954 and removing active labels.