Update selection cache when inserting items, too

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@53716 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/gtk/listbox.cpp

@@ -542,6 +542,8 @@ int wxListBox::DoInsertItems(const wxArrayStringsAdapter& items,
             AssignNewItemClientData(GtkGetIndexFor(itercur), clientData, i, type);
     }
 
+    UpdateOldSelections();
+
     return pos + numItems - 1;
 }