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

chrome/browser/download/download_path_reservation_tracker.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/download/download_path_reservation_tracker.h"
 
 #include <map>
 
 #include "base/bind.h"
 #include "base/callback.h"
 #include "base/file_util.h"
 #include "base/logging.h"
 #include "base/path_service.h"
 #include "base/stl_util.h"
-#include "base/string_util.h"
-#include "base/stringprintf.h"
+#include "base/strings/string_util.h"
+#include "base/strings/stringprintf.h"
 #include "base/third_party/icu/icu_utf.h"
 #include "chrome/browser/download/download_util.h"
 #include "chrome/common/chrome_paths.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/download_item.h"
 
 using content::BrowserThread;
 using content::DownloadItem;
 
 namespace {
@@ skipping 331 matching lines @@
       create_directory,
       conflict_action,
       callback));
 }
 
 // static
 bool DownloadPathReservationTracker::IsPathInUseForTesting(
     const base::FilePath& path) {
   return IsPathInUse(path);
 }