[Offline pages] Downloads UI: Adding bridge for issuing notifications

components/offline_pages/background/request_coordinator.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 COMPONENTS_OFFLINE_PAGES_BACKGROUND_REQUEST_COORDINATOR_H_
 #define COMPONENTS_OFFLINE_PAGES_BACKGROUND_REQUEST_COORDINATOR_H_
 
 #include <memory>
 
 #include "base/callback.h"
@@ skipping 34 matching lines @@
     RETRY_COUNT_EXCEEDED,
     REMOVED,
   };
 
   // Nested observer class.  To make sure that no events are missed, the client
   // code should first register for notifications, then |GetAllRequests|, and
   // ignore all events before the return from |GetAllRequests|, and consume
   // events after the return callback from |GetAllRequests|.
   class Observer {
    public:
+    virtual ~Observer() = default;
     virtual void OnAdded(const SavePageRequest& request) = 0;
     virtual void OnCompleted(const SavePageRequest& request,
                              SavePageStatus status) = 0;
     virtual void OnChanged(const SavePageRequest& request) = 0;
   };
 
   // Callback to report when the processing of a triggered task is complete.
   typedef base::Callback<void(const SavePageRequest& request)>
       RequestPickedCallback;
   typedef base::Callback<void()> RequestQueueEmptyCallback;
@@ skipping 177 matching lines @@
   base::TimeDelta offliner_timeout_;
   // Allows us to pass a weak pointer to callbacks.
   base::WeakPtrFactory<RequestCoordinator> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(RequestCoordinator);
 };
 
 }  // namespace offline_pages
 
 #endif  // COMPONENTS_OFFLINE_PAGES_BACKGROUND_REQUEST_COORDINATOR_H_