[gnome-builder] util: check for null before sink ref'ing variant

[Christian Hergert <chergert src gnome org>]

commit d4968bef56feacff3dfd32dbd1c1d63d33efa780
Author: Christian Hergert <christian hergert me>
Date:   Tue Jan 20 16:54:48 2015 -0800

    util: check for null before sink ref'ing variant

 src/util/gb-widget.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/src/util/gb-widget.c b/src/util/gb-widget.c
index df304d9..ff79c19 100644
--- a/src/util/gb-widget.c
+++ b/src/util/gb-widget.c
@@ -248,7 +248,7 @@ gb_widget_activate_action (GtkWidget   *widget,
         }
     }
 
-  if (g_variant_is_floating (parameter))
+  if (parameter && g_variant_is_floating (parameter))
     {
       parameter = g_variant_ref_sink (parameter);
       g_variant_unref (parameter);