iwyu: Use callback_old.h where appropriate, part 2.

net/disk_cache/disk_cache_test_util.h

 // Copyright (c) 2010 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 NET_DISK_CACHE_DISK_CACHE_TEST_UTIL_H_
 #define NET_DISK_CACHE_DISK_CACHE_TEST_UTIL_H_
 #pragma once
 
 #include <string>
 
-#include "base/callback.h"
+#include "base/callback_old.h"
 #include "base/file_path.h"
 #include "base/message_loop.h"
 #include "base/timer.h"
+#include "base/tuple.h"
 #include "build/build_config.h"
 
 // Re-creates a given test file inside the cache test folder.
 bool CreateCacheTestFile(const FilePath& name);
 
 // Deletes all file son the cache.
 bool DeleteCache(const FilePath& path);
 
 // Copies a set of cache files from the data folder to the test folder.
 bool CopyTestCache(const std::string& name);
@@ skipping 71 matching lines @@
   base::RepeatingTimer<MessageLoopHelper> timer_;
   int num_callbacks_;
   int num_iterations_;
   int last_;
   bool completed_;
 
   DISALLOW_COPY_AND_ASSIGN(MessageLoopHelper);
 };
 
 #endif  // NET_DISK_CACHE_DISK_CACHE_TEST_UTIL_H_