[gnome-robots/wip/libgames-support] Fix compiler warning

[Michael Catanzaro <mcatanzaro src gnome org>]

commit 50314125e12ac9977171b1b12dd4f8088600811d
Author: Michael Catanzaro <mcatanzaro gnome org>
Date:   Sat Sep 19 18:28:13 2015 -0500

    Fix compiler warning
    
    The return type has changed now that this has been ported to Vala

 src/gnome-robots.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/src/gnome-robots.c b/src/gnome-robots.c
index b0a2bff..c257910 100644
--- a/src/gnome-robots.c
+++ b/src/gnome-robots.c
@@ -375,7 +375,7 @@ activate (GtkApplication *app, gpointer user_data)
   g_signal_connect (G_OBJECT (game_area), "draw",
                    G_CALLBACK (draw_cb), NULL);
 
-  gridframe = games_grid_frame_new (GAME_WIDTH, GAME_HEIGHT);
+  gridframe = GTK_WIDGET(games_grid_frame_new (GAME_WIDTH, GAME_HEIGHT));
   gtk_container_add (GTK_CONTAINER (gridframe), game_area);
 
   hbox = gtk_box_new (GTK_ORIENTATION_HORIZONTAL, 0);