GTK: Make the gtk port compile with GTK_DISABLE_SINGLE_INCLUDES.

ui/gfx/insets.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 UI_GFX_INSETS_H_
 #define UI_GFX_INSETS_H_
 #pragma once
 
 #include <string>
 
 #include "build/build_config.h"
 #include "ui/base/ui_export.h"
 
 #if defined(TOOLKIT_USES_GTK)
-#include <gtk/gtkstyle.h>
+#include <gtk/gtk.h>
 #endif
 
 namespace gfx {
 
 //
 // An insets represents the borders of a container (the space the container must
 // leave at each of its edges).
 //
 
 class UI_EXPORT Insets {
@@ skipping 60 matching lines @@
  private:
   int top_;
   int left_;
   int bottom_;
   int right_;
 };
 
 }  // namespace gfx
 
 #endif  // UI_GFX_INSETS_H_