We can cache the associated security origin of the main frame for later use when a web page load is committed.
<rdar://problem/113720677>
Pull request: https://github.com/WebKit/WebKit/pull/16645
Committed 266870@main (015edd6245b9): <https://commits.webkit.org/266870@main> Reviewed commits have been landed. Closing PR #16645 and removing active labels.