[mutter/wayland] window-actor: Fix build

[Jasper St. Pierre <jstpierre src gnome org>]

commit c964ef4e012d7ba4ce88ec23fd0ab30f722a6dc4
Author: Jasper St. Pierre <jstpierre mecheye net>
Date:   Wed Feb 19 01:11:10 2014 -0500

    window-actor: Fix build
    
    I'm bad.

 src/compositor/meta-window-actor.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/src/compositor/meta-window-actor.c b/src/compositor/meta-window-actor.c
index be2514e..9456990 100644
--- a/src/compositor/meta-window-actor.c
+++ b/src/compositor/meta-window-actor.c
@@ -1685,7 +1685,7 @@ static void
 check_needs_x11_pixmap (MetaWindowActor *self)
 {
   MetaWindowActorPrivate *priv = self->priv;
-  MetaDisplay *display = meta_screen_get_display (screen);
+  MetaDisplay *display = meta_screen_get_display (priv->screen);
   Display *xdisplay = meta_display_get_xdisplay (display);
   Window xwindow  = meta_window_get_toplevel_xwindow (priv->window);