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

ui/views/controls/textfield/textfield.cc

 // 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.
 
 #include "ui/views/controls/textfield/textfield.h"
 
 #include <string>
 
 #include "base/command_line.h"
-#include "base/string_util.h"
+#include "base/strings/string_util.h"
 #include "base/strings/utf_string_conversions.h"
 #include "ui/base/accessibility/accessible_view_state.h"
 #include "ui/base/events/event.h"
 #include "ui/base/ime/text_input_type.h"
 #include "ui/base/keycodes/keyboard_codes.h"
 #include "ui/base/range/range.h"
 #include "ui/base/ui_base_switches.h"
 #include "ui/base/ui_base_switches_util.h"
 #include "ui/gfx/image/image_skia.h"
 #include "ui/gfx/insets.h"
@@ skipping 590 matching lines @@
 NativeTextfieldWrapper* NativeTextfieldWrapper::CreateWrapper(
     Textfield* field) {
 #if defined(OS_WIN) && !defined(USE_AURA)
   if (!Textfield::IsViewsTextfieldEnabled())
     return new NativeTextfieldWin(field);
 #endif
   return new NativeTextfieldViews(field);
 }
 
 }  // namespace views