2007-03-30  Elijah Newren  <newren gmail com>

	Add support for _NET_WM_USER_TIME_WINDOW in order to cut down on
	context switches.

	* src/display.c (meta_display_open):
	* src/display.h (struct _MetaDisplay):
	* src/screen.c (set_supported_hint):
	new atom

	* src/display.c (meta_display_open,
	  meta_display_get_current_time_roundtrip):
	* src/display.h (struct _MetaDisplay):
	create a dedicated timestamp pinging window instead of reusing
	display->leader_window

	* src/display.c (event_callback):
	* src/window-props.c (reload_net_wm_user_time_window):
	* src/window.c (meta_window_new_with_attrs, meta_window_free,
	  process_property_notify):
	* src/window.h (struct _MetaWindow):
	monitor property notify events on _NET_WM_USER_TIME_WINDOW windows too
	
	* src/window-props.[ch]:
	new meta_window_reload_propert(y|ies)_from_xwindow() functions

	* src/window-props.[ch]
	  (init_net_wm_user_time_window, reload_net_wm_user_time_window,
	  meta_display_init_window_prop_hooks):
	* src/window.c (meta_window_new_with_attrs):
	new hooks to handle new atom

svn path=/trunk/; revision=3134