Further porting of WebKit/ related types to the new IPC serialization format
<rdar://problem/105723213>
Pull request: https://github.com/WebKit/WebKit/pull/10444
Committed 260613@main (1d2ac11bafbd): <https://commits.webkit.org/260613@main> Reviewed commits have been landed. Closing PR #10444 and removing active labels.