Some clients, which use vidmode to change the resolution when going fullscreen,
create an override-redirect window and never trigger the screen->ResizeWindow
callback we rely on to do the xwl_window_check_resolution_change_emulation().

This causes us to not apply a viewport to them, causing the fullscreen window
to not fill the entire monitor.

This commit adds a call to xwl_window_check_resolution_change_emulation()
at the end of ensure_surface_for_window() to fix this. Note that
ensure_surface_for_window() exits early without creating an xwl_window
for new windows which will not be backed by a wayland surface and which
thus will not have an xwl_window.

This fixes ClanLib-0.6.x and alleggl-4.4.x using apps not properly
fullscreening.

Acked-by: Olivier Fourdan <ofourdan@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>