Break two classes defined in json_value_serializer.cc, .h into separate files.

chrome/installer/util/install_util.cc

 // Copyright (c) 2011 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.
 //
 // See the corresponding header file for description of the functions in this
 // file.
 
 #include "chrome/installer/util/install_util.h"
 
 #include <shellapi.h>
 #include <shlobj.h>
 #include <shlwapi.h>
 
 #include <algorithm>
 
 #include "base/command_line.h"
 #include "base/file_util.h"
-#include "base/json/json_value_serializer.h"
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/path_service.h"
 #include "base/string_util.h"
 #include "base/sys_info.h"
 #include "base/values.h"
 #include "base/version.h"
 #include "base/win/registry.h"
 #include "base/win/windows_version.h"
 #include "chrome/installer/util/browser_distribution.h"
@@ skipping 442 matching lines @@
   int len = GetDateFormatW(LOCALE_INVARIANT, 0, NULL, kDateFormat,
                            date_str, arraysize(date_str));
   if (len) {
     --len;  // Subtract terminating \0.
   } else {
     PLOG(DFATAL) << "GetDateFormat";
   }
 
   return std::wstring(date_str, len);
 }