Use a direct include of strings headers in ui/, part 3.

ui/views/controls/button/radio_button.h

 // Copyright (c) 2012 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_VIEWS_CONTROLS_BUTTON_RADIO_BUTTON_H_
 #define UI_VIEWS_CONTROLS_BUTTON_RADIO_BUTTON_H_
 
-#include "base/string16.h"
+#include "base/strings/string16.h"
 #include "ui/views/controls/button/checkbox.h"
 
 namespace views {
 
 // A native themed class representing a radio button.  This class does not use
 // platform specific objects to replicate the native platforms looks and feel.
 class VIEWS_EXPORT RadioButton : public Checkbox {
  public:
   // The button's class name.
   static const char kViewClassName[];
@@ skipping 17 matching lines @@
   // Overridden from Checkbox:
   virtual void SetChecked(bool checked) OVERRIDE;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(RadioButton);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_CONTROLS_BUTTON_RADIO_BUTTON_H_