Added AddDownload communication path and observers

chrome/browser/background_fetch/background_fetch_client_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 CHROME_BROWSER_BACKGROUND_FETCH_BACKGROUND_FETCH_CLIENT_IMPL_H_
 #define CHROME_BROWSER_BACKGROUND_FETCH_BACKGROUND_FETCH_CLIENT_IMPL_H_
 
 #include <string>
 
 #include "base/macros.h"
+#include "base/observer_list.h"
 #include "components/keyed_service/core/keyed_service.h"
 #include "components/offline_items_collection/core/offline_content_provider.h"
 #include "content/public/browser/background_fetch_client.h"
 
 namespace offline_items_collection {
 struct ContentId;
 struct OfflineItem;
 }  // namespace offline_items_collection
 
 class Profile;
 
 class BackgroundFetchClientImpl
     : public content::BackgroundFetchClient,
       public offline_items_collection::OfflineContentProvider,
       public KeyedService {
  public:
   explicit BackgroundFetchClientImpl(Profile* profile);
   ~BackgroundFetchClientImpl() override;
 
   // KeyedService override.
   void Shutdown() override;
 
   // content::BackgroundFetchClient implementation.
   void SetDelegate(content::BackgroundFetchClient::Delegate* delegate) override;
+  void AddDownload(const GURL& url,
+                   const std::string& registration_id,
+                   const std::string& title,
+                   int64_t total_download_size) override;
 
   // components::offline_items_collection::OfflineContentProvider overrides.
   bool AreItemsAvailable() override;
   void OpenItem(const offline_items_collection::ContentId& content_id) override;
   void RemoveItem(
       const offline_items_collection::ContentId& content_id) override;
   void CancelDownload(
       const offline_items_collection::ContentId& content_id) override;
   void PauseDownload(
       const offline_items_collection::ContentId& content_id) override;
   void ResumeDownload(
       const offline_items_collection::ContentId& content_id) override;
   const offline_items_collection::OfflineItem* GetItemById(
       const offline_items_collection::ContentId& content_id) override;
   offline_items_collection::OfflineContentProvider::OfflineItemList
   GetAllItems() override;
   void GetVisualsForItem(const offline_items_collection::ContentId& id,
                          const VisualsCallback& callback) override;
   void AddObserver(Observer* observer) override;
   void RemoveObserver(Observer* observer) override;
 
  private:
   // This object is owned by the Profile.
   Profile* profile_;
 
   // The |delegate| is owned externally and will remove itself prior to
   // deletion.
-  content::BackgroundFetchClient::Delegate* delegate_;
+  content::BackgroundFetchClient::Delegate* delegate_ = nullptr;

[Peter Beverloo, 2017/04/24 14:39:15]

Should probably merge this in the previous CL.

 
   // The name of the namespace registered with the aggregator.
   std::string namespace_;
 
+  // A list of all currently registered observers.
+  base::ObserverList<OfflineContentProvider::Observer> observers_;
+
   DISALLOW_COPY_AND_ASSIGN(BackgroundFetchClientImpl);
 };
 
 #endif  // CHROME_BROWSER_BACKGROUND_FETCH_BACKGROUND_FETCH_CLIENT_IMPL_H_