Use GimpContainer getters instead of poking into the class

instance struct.

* app/actions/context-commands.c
* app/actions/data-commands.c
* app/actions/plug-in-commands.c
* app/actions/templates-commands.c
* app/core/gimp-utils.c
* app/core/gimpdrawablestack.c
* app/core/gimpitemstack.c
* app/core/gimplist.c
* app/gui/gui-vtable.c
* app/widgets/gimpcontainerbox.c
* app/widgets/gimpcontainercombobox.c
* app/widgets/gimpcontainereditor.c
* app/widgets/gimpcontainerentry.c
* app/widgets/gimpcontainergridview.c
* app/widgets/gimpcontainerpopup.c
* app/widgets/gimpcontainertreeview-dnd.c
* app/widgets/gimpcontainertreeview.c
* app/widgets/gimpcontainerview-utils.c
* app/widgets/gimpcontainerview.c
* app/widgets/gimpdataeditor.c
* app/widgets/gimpdatafactoryview.c
* app/widgets/gimpsettingsbox.c
* app/widgets/gimpviewablebutton.c

svn path=/trunk/; revision=27693

app/widgets/gimpcontainerentry.c

@@ -297,7 +297,8 @@ gimp_container_entry_reorder_item (GimpContainerView *view,
   if (!iter)
     return;
 
-  if (new_index == -1 || new_index == container->num_children - 1)
+  if (new_index == -1 ||
+      new_index == gimp_container_get_n_children (container) - 1)
     {
       gtk_list_store_move_before (GTK_LIST_STORE (model), iter, NULL);
     }