Use a direct include of strings headers in chrome/browser/ui/a*/.

chrome/browser/ui/autofill/autofill_popup_controller.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 CHROME_BROWSER_UI_AUTOFILL_AUTOFILL_POPUP_CONTROLLER_H_
 #define CHROME_BROWSER_UI_AUTOFILL_AUTOFILL_POPUP_CONTROLLER_H_
 
 #include <vector>
 
 #include "base/compiler_specific.h"
-#include "base/string16.h"
+#include "base/strings/string16.h"
 #include "ui/gfx/native_widget_types.h"
 
 namespace gfx {
 class Font;
 class Point;
 class Rect;
 class RectF;
 }
 
 namespace autofill {
@@ skipping 71 matching lines @@
   // hovered or has keyboard focus.
   virtual int selected_line() const = 0;
 
  protected:
   virtual ~AutofillPopupController() {}
 };
 
 }  // namespace autofill
 
 #endif  // CHROME_BROWSER_UI_AUTOFILL_AUTOFILL_POPUP_CONTROLLER_H_