[CleanUp] Remove parameter |by_user| in NotificationClosed

content/browser/notifications/page_notification_delegate.h

 // Copyright 2014 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 CONTENT_BROWSER_NOTIFICATIONS_PAGE_NOTIFICATION_DELEGATE_H_
 #define CONTENT_BROWSER_NOTIFICATIONS_PAGE_NOTIFICATION_DELEGATE_H_
 
 #include "content/public/browser/desktop_notification_delegate.h"
 
 namespace content {
 
 // A delegate used by the notification service to report the results of platform
 // notification interactions to Web Notifications whose lifetime is tied to
 // that of the page displaying them.
 class PageNotificationDelegate : public DesktopNotificationDelegate {
  public:
   PageNotificationDelegate(int render_process_id, int notification_id);
   ~PageNotificationDelegate() override;
 
   // DesktopNotificationDelegate implementation.
   void NotificationDisplayed() override;
-  void NotificationClosed(bool by_user) override;
+  void NotificationClosed() override;
   void NotificationClick() override;
 
  private:
   int render_process_id_;
   int notification_id_;
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_NOTIFICATIONS_PAGE_NOTIFICATION_DELEGATE_H_