mTimers->AddItem( &aTimer );
mTimers.AddItem( &aTimer );
nsresult TimerPeriodical::AddTimer( TimerImpl * aTimer){	try	{		NS_ADDREF(aTimer);		mTimers->AddItem( &aTimer );		StartRepeating();	}	catch(...)	{		return NS_ERROR_UNEXPECTED;	}	return NS_OK;}