There's even more we could do in this direction.

	* components/music/nautilus-music-view.c:
	(nautilus_music_view_initialize): Got rid of redundant background
	color initialization.
	(nautilus_music_view_realize): Got rid of background color
	initialization.
	(nautilus_music_view_update_from_uri): Changed background color
	handling to use new nautilus_directory_background calls.
	(nautilus_music_view_background_changed): Not needed any more.

	* components/notes/ntl-notes.c:
	Did some cleanup and reformatting.

	* libnautilus/Makefile.am:
	* libnautilus/nautilus-directory-background.c:
	* libnautilus/nautilus-directory-background.h:
	Created a new file with functions that manage the background for
	a window connected with a particular directory. Later we might
	generalize it further to work for windows that are connected to
	any URI, not just a directory.

	* libnautilus/nautilus-directory.c:
	* libnautilus/nautilus-directory.h:
	Added a new "metdata_changed" signal so that the background can
	be updated if the underlying data changes.
	(nautilus_directory_initialize_class): Create the new signal.
	(nautilus_directory_ref), (nautilus_directory_unref): Made these
	functions quietly do nothing for NULL. This simplifies life for
	callers.
	(nautilus_directory_set_metadata): Emit the "metadata_changed"
	signal.

	* libnautilus/nautilus-file.c:
	(nautilus_file_ref), (nautilus_file_unref): Made these
	functions quietly do nothing for NULL. This simplifies life for
	callers.

	* libnautilus/nautilus-metadata.h:
	Renamed all the constants to be consistent. Got rid of separate
	constants for the icon view and list view backgrounds. Changed
	some of the underlying XML tags as well.

	* libnautilus/nautilus-icon-factory.c:
	(nautilus_icon_factory_get_icon_for_file):
	* src/nautilus-index-title.c: (nautilus_index_title_update_info):
	* src/ntl-index-panel: (nautilus_index_panel_update_info),
	(receive_dropped_uri_list),
	(nautilus_index_panel_background_changed):
	* src/ntl-uri-map.c: (set_initial_content_iid),
	(add_components_from_metadata):
	* src/ntl-window-msgs.c: (view_menu_switch_views_cb):
	* src/file-manager/fm-icon-view.c: (add_icon_if_already_positioned),
	(fm_icon_view_begin_loading), (fm_icon_view_set_zoom_level),
	(fm_icon_view_icon_changed_callback):
	* src/file-manager/fm-list-view.c: (fm_list_view_begin_loading),
	(fm_list_view_set_zoom_level), (fm_list_view_sort_items):
	Updated uses of metadata constants to use the new names.

	* src/ntl-index-panel: (nautilus_index_panel_destroy),
	(nautilus_index_panel_update_info):
	* src/ntl-uri-map.c: (add_components_from_metadata):
	* src/file-manager/fm-directory-view.c:
	(fm_directory_view_destroy), (fm_directory_view_load_uri):
	Used new nautilus_directory_unref to simplify code.

	* src/ntl-uri-map.c: (set_initial_content_iid):
	* src/ntl-window-msgs.c: (view_menu_switch_views_cb):
	Added missing nautilus_directory_unref (storage leak).

	* src/file-manager/fm-icon-view.c: (create_icon_container),
	(fm_icon_view_background_changed_callback): Removed "changed"
	signal handler on NautilusBackground since that's now handled
	by the new nautilus_directory_background calls instead.
	(fm_icon_view_begin_loading): Used nautilus_directory_background
	to replace background customization code.

	* src/file-manager/fm-icon-view.c: (fm_icon_view_get_zoom_level):
	Fixed a bug where it would try to use view as an FMIconView after
	the FM_IS_ICON_VIEW check failed.

	* src/file-manager/fm-list-view.c: (create_list),
	(fm_list_view_background_changed_callback): Removed "changed"
	signal handler on NautilusBackground since that's now handled
	by the new nautilus_directory_background calls instead.
	(fm_list_view_begin_loading): Used nautilus_directory_background
	to replace background customization code.