* components/tree/nautilus-tree-model.h:
	* components/tree/nautilus-tree-model.c: (tree_node_destroy),
	(tree_node_get_pixbuf_from_factory), (tree_node_update_pixbuf),
	(tree_node_update_closed_pixbuf), (tree_node_update_open_pixbuf),
	(tree_node_get_closed_pixbuf), (tree_node_get_open_pixbuf),
	(update_node_without_reporting),
	(nautilus_tree_model_get_column_type),
	(nautilus_tree_model_get_value):
	Added open pixbuf support.

	* components/tree/nautilus-tree-view.c: (save_expansion_state):
	Fix storage leak.
	(row_activated_callback): Fix NautilusFile ref. count leak.
	(create_tree): Pass in open pixbuf for "pixbuf_expander_open".
	(get_filtering_as_integer), (update_filtering_from_preferences),
	(filtering_changed_callback), (nautilus_tree_view_instance_init),
	(nautilus_tree_view_finalize): Starting on code needed to
	respect the filtering preferences.