[gtk+] Include OS X system headers

[Benjamin Otte <otte src gnome org>]

commit cadcd029a1dad1d508fb0019d7e4697ac2513d51
Author: Kristian Rietveld <kris gtk org>
Date:   Tue Sep 14 08:16:54 2010 +0200

    Include OS X system headers

 gdk/quartz/gdkdrawable-quartz.h |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)
---
diff --git a/gdk/quartz/gdkdrawable-quartz.h b/gdk/quartz/gdkdrawable-quartz.h
index 1e5c8e8..80c351a 100644
--- a/gdk/quartz/gdkdrawable-quartz.h
+++ b/gdk/quartz/gdkdrawable-quartz.h
@@ -23,6 +23,8 @@
 
 #include <gdk/gdkdrawable.h>
 
+#include <AppKit/AppKit.h>
+
 G_BEGIN_DECLS
 
 /* Drawable implementation for Quartz