[mutter] Fix build error introduced by d482590c84

[Adel Gadllah <agadllah src gnome org>]

commit a362c08f4e6f70d6a8063efba8ae94380b5cdbde
Author: Adel Gadllah <adel gadllah gmail com>
Date:   Sat Feb 9 17:00:40 2013 +0100

    Fix build error introduced by d482590c84

 src/core/window.c |    3 ---
 1 files changed, 0 insertions(+), 3 deletions(-)
---
diff --git a/src/core/window.c b/src/core/window.c
index 1a4c680..aa5a006 100644
--- a/src/core/window.c
+++ b/src/core/window.c
@@ -6321,9 +6321,6 @@ meta_window_change_workspace_by_index (MetaWindow *window,
 #define _NET_WM_MOVERESIZE_MOVE_KEYBOARD    10
 #define _NET_WM_MOVERESIZE_CANCEL           11
 
-/* Copied from the old gtk+/xi2 branch */
-#define XIMaskIsSet(ptr, bit) (((unsigned char *) (ptr))[(bit) >> 3] & (1 << ((bit) & 7)))
-
 gboolean
 meta_window_client_message (MetaWindow *window,
                             XEvent     *event)