(void) obs->OnChange(aSource, aProperty, aOldTarget, aNewTarget);
(void) obs->OnChange(this, aSource, aProperty, aOldTarget, aNewTarget);
nsBookmarksService::OnChange(nsIRDFResource* aSource,			     nsIRDFResource* aProperty,			     nsIRDFNode* aOldTarget,			     nsIRDFNode* aNewTarget){	if (mObservers) {		nsresult rv;		PRUint32 count;		rv = mObservers->Count(&count);		if (NS_FAILED(rv)) return rv;		for (PRInt32 i = 0; i < PRInt32(count); ++i) {			nsIRDFObserver* obs =				NS_REINTERPRET_CAST(nsIRDFObserver*, mObservers->ElementAt(i));			(void) obs->OnChange(aSource, aProperty, aOldTarget, aNewTarget);			NS_RELEASE(obs);		}	}	return NS_OK;}