Launch the new process a bit earlier when doing a COOP process-swap for better performance. Also use the leverage the prewarmed WebProcess when available.
Created attachment 438825 [details]
Created attachment 438853 [details]
Committed r282854 (241985@main): <https://commits.webkit.org/241985@main>
All reviewed patches have been landed. Closing bug and clearing flags on attachment 438853 [details].