NautilusFile, NautilusDirectory, and NautilusScalableIcon.

	* components/tree/nautilus-tree-model.c: (remove_all_nodes):
	Unref the root node when we are done with it.
	(report_root_node_if_possible): Use report_node_changed for
	new nodes as well.
	(report_node_changed): Since a new node and a changed node are
	really the same, just use this instead of using a different call
	for added vs. changed.
	(nautilus_tree_model_directory_files_changed_callback): Ref
	the node when it's being added to the hash table. Get rid of
	the misguided code that would ref "because remove will unref"
	and instead use a more normal model.
	(nautilus_tree_model_directory_files_added_callback): Fix a
	storage leak in the case where we generate a warning. Changed it
	from a printf to a g_warning. Use report_node_changed for new
	nodes as well. Unref the node after adding it to use a more normal
	ref model; handles cases where it's already in there properly, for
	one thing.
	* components/tree/nautilus-tree-node.c:
	(nautilus_tree_node_set_parent): Changed an assert to a
	return_if_fail.

	* libnautilus-extensions/nautilus-bookmark.c:
	(nautilus_bookmark_update_icon): Change the code to take the fact
	that nautilus_icon_factory_get_icon_for_file yields a new ref into
	account to plug a NautilusScalableIcon leak.

	* src/nautilus-bookmark-parsing.c:
	(nautilus_bookmark_new_from_node): Unref the icon after creating a
	new bookmark. If the bookmark needs to keep it, it will ref it.

	* src/file-manager/fm-icon-view.c: (get_icon_images_callback):
	Extra space in here.