Use a direct include of strings headers in x/.

chrome/browser/ui/views/extensions/browser_action_drag_data.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 "chrome/browser/ui/views/extensions/browser_action_drag_data.h"
 
 #include "base/logging.h"
 #include "base/pickle.h"
-#include "base/string_util.h"
+#include "base/strings/string_util.h"
 #include "chrome/browser/profiles/profile.h"
 #include "ui/base/clipboard/clipboard.h"
 
 const char* BrowserActionDragData::kClipboardFormatString =
     "chromium/x-browser-actions";
 
 BrowserActionDragData::BrowserActionDragData()
     : profile_(NULL), index_(-1) {
 }
 
@@ skipping 59 matching lines @@
   if (!pickle->ReadString(&data_iterator, &id_))
     return false;
 
   uint64 index;
   if (!pickle->ReadUInt64(&data_iterator, &index))
     return false;
   index_ = static_cast<size_t>(index);
 
   return true;
 }