[mutter] display: Add an extra check inside meta_display_close

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

commit f9d33b2efc00267e9b6ab8a4721258a0a2312df7
Author: Jasper St. Pierre <jstpierre mecheye net>
Date:   Sun Jul 13 11:36:34 2014 -0400

    display: Add an extra check inside meta_display_close
    
    For clarity of what the expected input to this function is.

 src/core/display.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
---
diff --git a/src/core/display.c b/src/core/display.c
index c5f412e..228f512 100644
--- a/src/core/display.c
+++ b/src/core/display.c
@@ -1015,6 +1015,7 @@ meta_display_close (MetaDisplay *display,
                     guint32      timestamp)
 {
   g_assert (display != NULL);
+  g_assert (display == the_display);
 
   if (display->closing != 0)
     {