This is one of steps to make an Isolate parameter mandatory.
Created attachment 182547 [details] Patch
Comment on attachment 182547 [details] Patch Sorry. Misclick.
Comment on attachment 182547 [details] Patch Clearing flags on attachment: 182547 Committed r139621: <http://trac.webkit.org/changeset/139621>
All reviewed patches have been landed. Closing bug.