[mutter/wayland] display: Fix compiler warning

[Florian Müllner <fmuellner src gnome org>]

commit 71be7e8493759cd75f556d83d866f9188d3c3bfe
Author: Florian Müllner <fmuellner gnome org>
Date:   Tue Mar 25 16:27:09 2014 +0100

    display: Fix compiler warning
    
    Don't leave a variable uninitialized in case we don't find a matching
    surface.

 src/core/display.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/src/core/display.c b/src/core/display.c
index 4f6de93..c63f2ce 100644
--- a/src/core/display.c
+++ b/src/core/display.c
@@ -1629,7 +1629,7 @@ void
 meta_display_sync_wayland_input_focus (MetaDisplay *display)
 {
   MetaWaylandCompositor *compositor = meta_wayland_compositor_get_default ();
-  MetaWindow *focus_window;
+  MetaWindow *focus_window = NULL;
 
   if (meta_grab_op_is_wayland (display->grab_op))
     focus_window = NULL;