Interface used as a callback for listening to events.
[scriptable, function, uuid(2dfe3a50-ab2f-11db-abbd-0800200c9a66)]
interface extIEventListener : nsISupports

Methods

 This method is called whenever an event occurs of the type for which 
 the extIEventListener interface was registered.

 @param   aEvent
          The extIEventItem associated with the event.
void handleEvent(in extIEventItem aEvent)