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

ui/views/controls/textfield/native_textfield_wrapper.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_TEXTFIELD_NATIVE_TEXTFIELD_WRAPPER_H_
 #define UI_VIEWS_CONTROLS_TEXTFIELD_NATIVE_TEXTFIELD_WRAPPER_H_
 
-#include "base/string16.h"
 #include "base/i18n/rtl.h"
+#include "base/strings/string16.h"
 #include "ui/base/range/range.h"
 #include "ui/gfx/native_widget_types.h"
 #include "ui/gfx/selection_model.h"
 #include "ui/gfx/text_constants.h"
 #include "ui/views/views_export.h"
 
 namespace gfx {
 class Insets;
 }  // namespace gfx
 
@@ skipping 161 matching lines @@
   // Returns whether there is a drag operation originating from the textfield.
   virtual bool HasTextBeingDragged() = 0;
 
   // Creates an appropriate NativeTextfieldWrapper for the platform.
   static NativeTextfieldWrapper* CreateWrapper(Textfield* field);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_CONTROLS_TEXTFIELD_NATIVE_TEXTFIELD_WRAPPER_H_