private void OnEndFactorizedEvents(NotifyCollectionChangedEventArgs e)
        {
            _FE = null;
            if (e == null)
                return;

            EmitEvent(e,true);
        }
        internal IDisposable GetEventFactorizable()
        {
            if (_FE == null)
                _FE = new EventsFactorizer(this);

            return _FE;
        }