Prepare to abstract PersistedData by making it part of the configurator.

components/update_client/update_engine.cc

 // Copyright 2015 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 "components/update_client/update_engine.h"
 
 #include <utility>
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
@@ skipping 40 matching lines @@
 UpdateEngine::UpdateEngine(
     const scoped_refptr<Configurator>& config,
     UpdateChecker::Factory update_checker_factory,
     CrxDownloader::Factory crx_downloader_factory,
     PingManager* ping_manager,
     const NotifyObserversCallback& notify_observers_callback)
     : config_(config),
       update_checker_factory_(update_checker_factory),
       crx_downloader_factory_(crx_downloader_factory),
       ping_manager_(ping_manager),
-      metadata_(new PersistedData(config->GetPrefService())),
+      metadata_(std::move(config->CreateMetadata())),

[waffles, 2017/05/15 17:52:19]

remove std::move. (moving a temporary object prevents copy elision)

       notify_observers_callback_(notify_observers_callback) {}
 
 UpdateEngine::~UpdateEngine() {
   DCHECK(thread_checker_.CalledOnValidThread());
 }
 
 void UpdateEngine::Update(
     bool is_foreground,
     const std::vector<std::string>& ids,
     const UpdateClient::CrxDataCallback& crx_data_callback,
@@ skipping 289 matching lines @@
   component->Uninstall(version, reason);
 
   update_context->component_queue.push(id);
 
   base::ThreadTaskRunnerHandle::Get()->PostTask(
       FROM_HERE,
       base::Bind(&UpdateEngine::HandleComponent, base::Unretained(this), it));
 }
 
 }  // namespace update_client