Refactor Reading List Model to use URL as key.

ios/chrome/browser/reading_list/reading_list_download_service.h

 // Copyright 2016 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 IOS_CHROME_BROWSER_READING_LIST_READING_LIST_DOWNLOAD_SERVICE_H_
 #define IOS_CHROME_BROWSER_READING_LIST_READING_LIST_DOWNLOAD_SERVICE_H_
 
 #include "base/macros.h"
 #include "components/keyed_service/core/keyed_service.h"
 #include "ios/chrome/browser/reading_list/reading_list_model_observer.h"
@@ skipping 28 matching lines @@
   ~ReadingListDownloadService() override;
 
   // Initializes the reading list download service.
   void Initialize();
 
   // KeyedService implementation.
   void Shutdown() override;
 
   // ReadingListModelObserver implementation
   void ReadingListModelLoaded(const ReadingListModel* model) override;
-  void ReadingListWillRemoveReadEntry(const ReadingListModel* model,
-                                      size_t index) override;
-  void ReadingListWillRemoveUnreadEntry(const ReadingListModel* model,
-                                        size_t index) override;
-  void ReadingListWillAddUnreadEntry(const ReadingListModel* model,
-                                     const ReadingListEntry& entry) override;
-  void ReadingListWillAddReadEntry(const ReadingListModel* model,
-                                   const ReadingListEntry& entry) override;
+  void ReadingListWillRemoveEntry(const ReadingListModel* model,
+                                  const GURL& url) override;
+  void ReadingListWillAddEntry(const ReadingListModel* model,
+                               const ReadingListEntry& entry) override;
 
  private:
   // Tries to save offline versions of all entries in the reading list that are
   // not yet saved. Must only be called after reading list model is loaded.
   void DownloadAllEntries();
   // Schedule a download of an offline version of the reading list entry,
   // according to the delay of the entry. Must only be called after reading list
   // model is loaded.
   void ScheduleDownloadEntry(const ReadingListEntry& entry);
   // Tries to save an offline version of the reading list entry corresponding to
@@ skipping 28 matching lines @@
   std::vector<GURL> url_to_download_cellular_;
   std::vector<GURL> url_to_download_wifi_;
   bool had_connection_;
 
   base::WeakPtrFactory<ReadingListDownloadService> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(ReadingListDownloadService);
 };
 
 #endif  // IOS_CHROME_BROWSER_READING_LIST_READING_LIST_DOWNLOAD_SERVICE_H_