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

chrome/browser/devtools/devtools_file_helper.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_DEVTOOLS_DEVTOOLS_FILE_HELPER_H_
 #define CHROME_BROWSER_DEVTOOLS_DEVTOOLS_FILE_HELPER_H_
 
 #include <map>
 #include <string>
 #include <vector>
 
 #include "base/basictypes.h"
 #include "base/callback.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
-#include "base/string16.h"
+#include "base/strings/string16.h"
 
 class Profile;
 
 namespace base {
 class FilePath;
 }
 
 namespace content {
 class WebContents;
 }
@@ skipping 80 matching lines @@
 
   content::WebContents* web_contents_;
   Profile* profile_;
   base::WeakPtrFactory<DevToolsFileHelper> weak_factory_;
   typedef std::map<std::string, base::FilePath> PathsMap;
   PathsMap saved_files_;
   DISALLOW_COPY_AND_ASSIGN(DevToolsFileHelper);
 };
 
 #endif  // CHROME_BROWSER_DEVTOOLS_DEVTOOLS_FILE_HELPER_H_