Small fix : this array would get bigger with duplicate entries every time an event is dispatched
Fixes #855 : The event phase AT_TARGET should also fire events registered with capture=true on the event target, not just capture=false.
Note that calling stopPropagation should during AT_TARGET should not prevent any listeners registered on that same event target from being called.
As per spec, before and after an event has been dispatched, Event.eventPhase should be set to NONE and Event.currentTarget should be set to null.