[gnome-initial-setup] language: don't call g_variant_dup_string() on a NULL variant

[Cosimo Cecchi <cosimoc src gnome org>]

commit 7103c81df1bc5507ebd4313814390e9199af005b
Author: Cosimo Cecchi <cosimo endlessm com>
Date:   Tue Sep 16 17:14:37 2014 -0700

    language: don't call g_variant_dup_string() on a NULL variant
    
    g_dbus_proxy_get_cached_property() can return NULL. Guard against that
    case.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=736776

 .../pages/language/cc-common-language.c            |    8 ++++++--
 1 files changed, 6 insertions(+), 2 deletions(-)
---
diff --git a/gnome-initial-setup/pages/language/cc-common-language.c 
b/gnome-initial-setup/pages/language/cc-common-language.c
index c666905..d09232e 100644
--- a/gnome-initial-setup/pages/language/cc-common-language.c
+++ b/gnome-initial-setup/pages/language/cc-common-language.c
@@ -160,10 +160,14 @@ get_lang_for_user_object_path (const char *path)
                g_error_free (error);
                return NULL;
        }
+
+       lang = NULL;
        props = g_dbus_proxy_get_cached_property (user, "Language");
-       lang = g_variant_dup_string (props, NULL);
+       if (props != NULL) {
+               lang = g_variant_dup_string (props, NULL);
+               g_variant_unref (props);
+       }
 
-       g_variant_unref (props);
        g_object_unref (user);
        return lang;
 }