[gnome-builder] egg: clear signals on NULL toplevel

[Christian Hergert <chergert src gnome org>]

commit 595c11e080478f07962b803061376ec19f045ec7
Author: Christian Hergert <chergert redhat com>
Date:   Fri Nov 6 19:08:34 2015 -0800

    egg: clear signals on NULL toplevel

 contrib/egg/egg-centering-bin.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/contrib/egg/egg-centering-bin.c b/contrib/egg/egg-centering-bin.c
index 02378db..a65d4c8 100644
--- a/contrib/egg/egg-centering-bin.c
+++ b/contrib/egg/egg-centering-bin.c
@@ -132,7 +132,7 @@ egg_centering_bin_hierarchy_changed (GtkWidget *widget,
    */
 
   toplevel = gtk_widget_get_toplevel (widget);
-  if (GTK_IS_WINDOW (toplevel))
+  if ((toplevel == NULL) || GTK_IS_WINDOW (toplevel))
     egg_signal_group_set_target (priv->signals, toplevel);
 }