delete m_listView in constraintsEvent()

CCBUG: 299077

plasma/applets/folderview/folderview.cpp

@@ -1244,6 +1244,7 @@ void FolderView::constraintsEvent(Plasma::Constraints constraints)
 
             delete m_iconWidget;
             delete m_dialog;
+            delete m_listView;
             m_iconWidget = 0;
             m_dialog = 0;
             m_listView = 0;