The refactor in bug #164015 added the parameters to the wrong payload, it is just a typo.
Created attachment 294229 [details] Patch
Comment on attachment 294229 [details] Patch Nice one!
Comment on attachment 294229 [details] Patch Clearing flags on attachment: 294229 Committed r208530: <http://trac.webkit.org/changeset/208530>
All reviewed patches have been landed. Closing bug.