Make sure a controllerchange event gets fired on clients when a service worker gets deleted. This matches Firefox and Chrome's behavior.
Pull request: https://github.com/WebKit/WebKit/pull/14032
Committed 264255@main (3ebf7a86bf38): <https://commits.webkit.org/264255@main> Reviewed commits have been landed. Closing PR #14032 and removing active labels.
<rdar://problem/109567316>