[gtk+] Drop an unneeded include

[Matthias Clasen <matthiasc src gnome org>]

commit f60b2a11c5d77af9f59fb079c9695d44b9d9c3de
Author: Matthias Clasen <mclasen redhat com>
Date:   Thu Nov 6 15:17:09 2014 -0500

    Drop an unneeded include

 gtk/gtkpopovermenu.c |    1 -
 1 files changed, 0 insertions(+), 1 deletions(-)
---
diff --git a/gtk/gtkpopovermenu.c b/gtk/gtkpopovermenu.c
index 7947eb2..0bd1c0a 100644
--- a/gtk/gtkpopovermenu.c
+++ b/gtk/gtkpopovermenu.c
@@ -18,7 +18,6 @@
 #include "config.h"
 #include "gtkpopovermenu.h"
 #include "gtkstack.h"
-#include "gtkbox.h"
 #include "gtkintl.h"