[gtk+/broadway: 59/71] [broadway] Avoid crash if mask is NULL

[Alexander Larsson <alexl src gnome org>]

commit 7667ad456bf24b145d6f5b61e58c0d9f37f1e357
Author: Alexander Larsson <alexl redhat com>
Date:   Thu Nov 25 12:40:33 2010 +0100

    [broadway] Avoid crash if mask is NULL

 gdk/broadway/gdkwindow-broadway.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)
---
diff --git a/gdk/broadway/gdkwindow-broadway.c b/gdk/broadway/gdkwindow-broadway.c
index f09a12f..818ffac 100644
--- a/gdk/broadway/gdkwindow-broadway.c
+++ b/gdk/broadway/gdkwindow-broadway.c
@@ -872,7 +872,8 @@ _gdk_windowing_window_at_device_position (GdkDisplay      *display,
       private = (GdkWindowObject *)window;
       *win_x = display_broadway->last_x - private->x;
       *win_y = display_broadway->last_y - private->y;
-      *mask = 0;
+      if (mask)
+	*mask = 0;
     }
 
   return window;