void addEventListener(
    in DOMString type, 
    in EventListener listener, 
    in boolean useCapture); 

boolean dispatchEvent(
    in Event evt) raises(EventException); 

void removeEventListener(
    in DOMString type, 
    in EventListener listener, 
    in boolean useCapture); 

void swapCache() raises(DOMException); 

void update() raises(DOMException); 

const unsigned short CHECKING = 2; 

const unsigned short DOWNLOADING = 3; 

const unsigned short IDLE = 1; 

const unsigned short OBSOLETE = 5; 

attribute EventListener oncached; 

attribute EventListener onchecking; 

attribute EventListener ondownloading; 

attribute EventListener onerror; 

attribute EventListener onnoupdate; 

attribute EventListener onobsolete; 

attribute EventListener onprogress; 

attribute EventListener onupdateready; 

readonly attribute unsigned short status; 

const unsigned short UNCACHED = 0; 

const unsigned short UPDATEREADY = 4;