GTK: Make the gtk port compile with GTK_DISABLE_SINGLE_INCLUDES.

chrome/browser/ui/gtk/gtk_input_event_box.h

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CHROME_BROWSER_UI_GTK_GTK_INPUT_EVENT_BOX_H_
 #define CHROME_BROWSER_UI_GTK_GTK_INPUT_EVENT_BOX_H_
 #pragma once
 
-#include <gdk/gdk.h>
 #include <gtk/gtk.h>
 
 // GtkInputEventBox is like GtkEventBox, but with the following differences:
 //  1. Only supports input (like gtk_event_box_set_visible_window(foo, FALSE).
 //  2. Provides a method to get the GdkWindow (gtk_input_event_box_get_window).
 //  (The GdkWindow created by GtkEventBox cannot be retrieved unless you use it
 //  in visible mode.)
 // TODO(mattm): Get rid of this class someday if Gtk adds a way to get the
 // GtkEventBox event_window (https://bugzilla.gnome.org/show_bug.cgi?id=657380).
 
@@ skipping 30 matching lines @@
 GType gtk_input_event_box_get_type();
 GtkWidget* gtk_input_event_box_new();
 
 // Get the GdkWindow |widget| uses for handling input events. Will be NULL if
 // the widget has not been realized yet.
 GdkWindow* gtk_input_event_box_get_window(GtkInputEventBox* widget);
 
 G_END_DECLS
 
 #endif  // CHROME_BROWSER_UI_GTK_GTK_INPUT_EVENT_BOX_H_