QmlDesigner.statesEditor: fix going back to base state

forwarding to QmlModelView::customNotification(); was missing

it missing since ever but the code I removed in
861981a3 shadowed this.

Reviewed-by: Kai Koehne

src/plugins/qmldesigner/components/stateseditor/stateseditorview.cpp

@@ -391,11 +391,12 @@ void StatesEditorView::otherPropertyChanged(const QmlObjectNode &qmlObjectNode,
 }
 
 
-void StatesEditorView::customNotification(const AbstractView * /*view*/, const QString & /*identifier*/, const QList<ModelNode> & /*nodeList*/, const QList<QVariant> & /*data*/)
+void StatesEditorView::customNotification(const AbstractView * view, const QString & identifier, const QList<ModelNode> & nodeList, const QList<QVariant> & data)
 {
     if (debug)
         qDebug() << __FUNCTION__;
 
+    QmlModelView::customNotification(view, identifier, nodeList, data);
 }
 
 QPixmap StatesEditorView::renderState(int i)