Apply XAtom revork patches from Julien Danjou.

Apply XAtom revork patches from Julien Danjou.

* xsettings.c (init_xsettings): Use already fetch atoms.

* xsmfns.c (create_client_leader_window): Use SM_CLIENT_ID atom
from dpyinfo.

* xselect.c (Fx_send_client_event): Split and create
x_send_client_event.

* lisp.h: Do not EXFUN Fx_send_client_event.

* xterm.c (x_set_frame_alpha): Use _NET_WM_WINDOW_OPACITY atom
from dpyinfo.
(wm_supports): Use atoms from dpyinfo.
(do_ewmh_fullscreen): Use atoms from dpyinfo.
(x_ewmh_activate_frame): Use atoms from dpyinfo.
(xembed_set_info): Use atoms from dpyinfo.
(x_term_init): Fetch _XEMBED_INFO, _NET_SUPPORTED,
_NET_SUPPORTING_WM_CHECK, _NET_WM_WINDOW_OPACITY and
_NET_ACTIVE_WINDOW, XSETTINGS  atoms.
Get all atoms in one round-trip.
(set_wm_state): Use x_send_client_event rather than
Fx_send_client_event, using Atom directly.
(x_ewmh_activate_frame): Ditto.
(x_set_sticky): Pass atoms to set_wm_state.
(do_ewmh_fullscreen): Ditto.

* xterm.h (x_display_info): Add Xatom_net_supported,
Xatom_net_supporting_wm_check, Xatom_net_active_window,
Xatom_net_wm_window_opacity, Xatom_XEMBED_INFO, SM_CLIENT_ID.

* xfns.c (Fx_show_tip): Fix typo in docstring.