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

chrome/browser/extensions/extension_service_unittest.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/extensions/extension_service_unittest.h"
 
 #include <algorithm>
 #include <set>
 #include <vector>
 
 #include "base/basictypes.h"
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/file_util.h"
+#include "base/json/json_file_value_serializer.h"
 #include "base/json/json_reader.h"
-#include "base/json/json_value_serializer.h"
+#include "base/json/json_string_value_serializer.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
 #include "base/message_loop.h"
 #include "base/path_service.h"
 #include "base/scoped_temp_dir.h"
 #include "base/stl_util.h"
 #include "base/string16.h"
 #include "base/string_number_conversions.h"
 #include "base/string_util.h"
 #include "base/utf_string_conversions.h"
@@ skipping 4757 matching lines @@
   ASSERT_FALSE(AddPendingSyncInstall());
 
   // Wait for the external source to install.
   WaitForCrxInstall(crx_path_, INSTALL_NEW);
   ASSERT_TRUE(IsCrxInstalled());
 
   // Now that the extension is installed, sync request should fail
   // because the extension is already installed.
   ASSERT_FALSE(AddPendingSyncInstall());
 }