a #GtkTreePath-struct pointing to the tree node whose children have been reordered
a valid #GtkTreeIter-struct pointing to the node whose children have been reordered, or %NULL if the depth of @path is 0
an array of integers mapping the current position of each child to its old position before the re-ordering, i.e. @new_order[newpos] = oldpos
3.10
Emits the #GtkTreeModel::rows-reordered signal on @tree_model.
This should be called by models when their rows have been reordered.