The interface function should be used instead. add/remove_event_listener methods are not duplicated also because they are skipped by the script generator because they receive an EventListener as argument. We need a special case for dispatch_event that is currently generated twice, a public version using the object type as first parameter and the private one used to implement the interface receiving the interface type as first argument.
Created attachment 215049 [details] Patch
Comment on attachment 215049 [details] Patch LGTM
Committed r158083: <http://trac.webkit.org/changeset/158083>