toplevel: require GdkSurface

diff --git a/gdk/gdktoplevel.c b/gdk/gdktoplevel.c
index 6d9e2a9955546e78699a052b521eccb01fb9476d..1cfeb2c448afd056183b73f3bf3641393a22386d 100644 (file)
--- a/gdk/gdktoplevel.c
+++ b/gdk/gdktoplevel.c
@@ -31,11 +31,7 @@
  * A #GdkToplevel is a freestanding toplevel surface.
  */
 
-
-/* FIXME: this can't have GdkSurface as a prerequisite
- * as long as GdkSurface implements this interface itself
- */
-G_DEFINE_INTERFACE (GdkToplevel, gdk_toplevel, G_TYPE_OBJECT)
+G_DEFINE_INTERFACE (GdkToplevel, gdk_toplevel, GDK_TYPE_SURFACE)
 
 static gboolean
 gdk_toplevel_default_present (GdkToplevel       *toplevel,