[Offline Pages] Two-step expiration in storage manager.

components/offline_pages/offline_page_model.h

 // Copyright 2015 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_OFFLINE_PAGE_MODEL_H_
 #define COMPONENTS_OFFLINE_PAGES_OFFLINE_PAGE_MODEL_H_
 
 #include <stdint.h>
 
 #include <map>
@@ skipping 200 matching lines @@
 
   // Checks that all of the offline pages have corresponding offline copies.
   // If a page is discovered to be missing an offline copy, its offline page
   // metadata will be removed and |OfflinePageDeleted| will be sent to model
   // observers.
   void CheckForExternalFileDeletion();
 
   // Marks pages as expired and removes their respective files from the archive
   // directory.
   void ExpirePages(const std::vector<int64_t>& offline_ids,
-                   const base::Time& expiration_time);
+                   const base::Time& expiration_time,
+                   const base::Callback<void(bool)>& callback) override;
 
   // Returns the policy controller.
   ClientPolicyController* GetPolicyController();
 
   // Methods for testing only:
   OfflinePageMetadataStore* GetStoreForTesting();
 
   OfflinePageStorageManager* GetStorageManager();
 
   bool is_loaded() const;
@@ skipping 140 matching lines @@
   std::unique_ptr<ArchiveManager> archive_manager_;
 
   base::WeakPtrFactory<OfflinePageModel> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(OfflinePageModel);
 };
 
 }  // namespace offline_pages
 
 #endif  // COMPONENTS_OFFLINE_PAGES_OFFLINE_PAGE_MODEL_H_