2005-12-29  Matthias Clasen  <mclasen@redhat.com>

	* gtk/gtktreedatalist.c: Use the slice allocater for
	GtkTreeDataSortHeader.

	* gtk/gtktreedatalist.h:
	* gtk/gtktreedatalist.c (_gtk_tree_data_list_set_header): New function.

	* gtk/gtktreemodelsort.c (gtk_tree_model_sort_set_sort_func):
	* gtk/gtkliststore.c (gtk_list_store_set_sort_func):
	* gtk/gtktreestore.c (gtk_tree_store_set_sort_func): Use it here.