[gtk+] gdk: Make GdkWindow abstract

[Matthias Clasen <matthiasc src gnome org>]

commit 36893a9ef8b724e283038f0d538c411cdd5b1ddb
Author: Benjamin Otte <otte redhat com>
Date:   Tue Dec 21 03:54:15 2010 +0100

    gdk: Make GdkWindow abstract
    
    This way backend implementors get an error if they don't set
    display_class->window_type to their subclass. And that's exactly what we
    want.

 gdk/gdkwindow.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/gdk/gdkwindow.c b/gdk/gdkwindow.c
index cb159e6..699d5dc 100644
--- a/gdk/gdkwindow.c
+++ b/gdk/gdkwindow.c
@@ -271,7 +271,7 @@ new_region_tag (void)
   return ++tag;
 }
 
-G_DEFINE_TYPE (GdkWindow, gdk_window, G_TYPE_OBJECT)
+G_DEFINE_ABSTRACT_TYPE (GdkWindow, gdk_window, G_TYPE_OBJECT)
 
 GType
 _gdk_paintable_get_type (void)