Add initial Controller to DownloadService

components/download/internal/model_impl.h

 // Copyright 2017 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 COMPONENTS_DOWNLOAD_INTERNAL_MODEL_IMPL_H_
 #define COMPONENTS_DOWNLOAD_INTERNAL_MODEL_IMPL_H_
 
 #include <map>
 #include <string>
 #include <utility>
 #include <vector>
 
 #include "base/macros.h"
 #include "base/memory/weak_ptr.h"
 #include "components/download/internal/model.h"
 #include "components/download/internal/store.h"
 #include "components/download/public/clients.h"
 
 namespace download {
 
 struct Entry;
 
 // The internal implementation of Model.
 class ModelImpl : public Model {
  public:
-  ModelImpl(Client* client, std::unique_ptr<Store> store);
+  ModelImpl(std::unique_ptr<Store> store);
   ~ModelImpl() override;
 
   // Model implementation.
-  void Initialize() override;
+  void Initialize(Client* client) override;
   void Add(const Entry& entry) override;
   void Update(const Entry& entry) override;
   void Remove(const std::string& guid) override;
   Entry* Get(const std::string& guid) override;
   EntryList PeekEntries() override;
 
  private:
   using OwnedEntryMap = std::map<std::string, std::unique_ptr<Entry>>;
 
   void OnInitializedFinished(bool success,
                              std::unique_ptr<std::vector<Entry>> entries);
   void OnAddFinished(DownloadClient client,
                      const std::string& guid,
                      bool success);
   void OnUpdateFinished(DownloadClient client,
                         const std::string& guid,
                         bool success);
   void OnRemoveFinished(DownloadClient client,
                         const std::string& guid,
                         bool success);
 
   // The external Model::Client reference that will receive all interesting
   // Model notifications.
-  Client* const client_;
+  Client* client_;
 
   // The backing Store that is responsible for saving and loading the
   // persisted entries.
   std::unique_ptr<Store> store_;
 
   // A map of [guid] -> [std::unique_ptr<Entry>].  Effectively the cache of the
   // entries saved in Store.
   OwnedEntryMap entries_;
 
   base::WeakPtrFactory<ModelImpl> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(ModelImpl);
 };
 
 }  // namespace download
 
 #endif  // COMPONENTS_DOWNLOAD_INTERNAL_MODEL_IMPL_H_