Only distill unread items

ios/chrome/browser/reading_list/url_downloader.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_URL_DOWNLOADER_H_
 #define IOS_CHROME_BROWSER_READING_LIST_URL_DOWNLOADER_H_
 
 #include <queue>
 
 #include "base/callback.h"
@@ skipping 50 matching lines @@
   URLDownloader(dom_distiller::DomDistillerService* distiller_service,
                 PrefService* prefs,
                 base::FilePath chrome_profile_path,
                 const DownloadCompletion& download_completion,
                 const SuccessCompletion& delete_completion);
   virtual ~URLDownloader();
 
   // Asynchronously download an offline version of the URL.
   void DownloadOfflineURL(const GURL& url);
 
+  // Cancels the download job an offline version of the URL.
+  void CancelDownloadOfflineURL(const GURL& url);
+
   // Asynchronously remove the offline version of the URL if it exists.
   void RemoveOfflineURL(const GURL& url);
 
  private:
   enum TaskType { DELETE, DOWNLOAD };
   using Task = std::pair<TaskType, GURL>;
 
   // Calls callback with true if an offline file exists for this URL.
   void OfflineURLExists(const GURL& url, base::Callback<void(bool)> callback);
   // Handles the next task in the queue, if no task is currently being handled.
@@ skipping 48 matching lines @@
   std::deque<Task> tasks_;
   bool working_;
   base::FilePath base_directory_;
   std::unique_ptr<dom_distiller::DistillerViewerInterface> distiller_;
   base::CancelableTaskTracker task_tracker_;
 
   DISALLOW_COPY_AND_ASSIGN(URLDownloader);
 };
 
 #endif  // IOS_CHROME_BROWSER_READING_LIST_URL_DOWNLOADER_H_