[gnome-screensaver] Fix compiler warning by adding GTK_WIDGET() cast

[Wouter Bolsterlee <wbolster src gnome org>]

commit 12e4f8420c6e94aa692cf56f3a1b898ba7ce7eb6
Author: Wouter Bolsterlee <wbolster gnome org>
Date:   Sun Jun 6 15:58:56 2010 +0200

    Fix compiler warning by adding GTK_WIDGET() cast

 src/gs-manager.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/src/gs-manager.c b/src/gs-manager.c
index c4e2076..aea72f3 100644
--- a/src/gs-manager.c
+++ b/src/gs-manager.c
@@ -1470,7 +1470,7 @@ gs_manager_create_window_for_monitor (GSManager *manager,
         manager->priv->windows = g_slist_append (manager->priv->windows, window);
 
         if (manager->priv->active && !manager->priv->fading) {
-                gtk_widget_show (window);
+                gtk_widget_show (GTK_WIDGET (window));
         }
 }