[Offline pages] Adding capability to free up space used by Offline pages

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 <map>
 #include <vector>
 
@@ skipping 107 matching lines @@
                               const DeletePageCallback& callback);
 
   // Deletes offline pages related to the passed |bookmark_ids|. Requires that
   // the model is loaded.
   void DeletePagesByBookmarkId(const std::vector<int64>& bookmark_ids,
                                const DeletePageCallback& callback);
 
   // Gets all available offline pages. Requires that the model is loaded.
   const std::vector<OfflinePageItem> GetAllPages() const;
 
+  // Gets pages that should be removed to clean up storage. Requires that the
+  // model is loaded.
+  const std::vector<OfflinePageItem> GetPagesToCleanUp() const;
+
   // Gets an offline page associated with a specified |bookmark_id|. Returns
   // true if a matching offline page exists, and |offline_page| will be updated
   // with corresponding value, or false, if no offline page was found.
   bool GetPageByBookmarkId(int64 bookmark_id,
                            OfflinePageItem* offline_page) const;
 
   // Returns an offline page that is stored as |offline_url|. nullptr is
   // returned if not found.
   const OfflinePageItem* GetPageByOfflineURL(const GURL& offline_url) const;
 
@@ skipping 52 matching lines @@
   PendingArchivers pending_archivers_;
 
   base::WeakPtrFactory<OfflinePageModel> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(OfflinePageModel);
 };
 
 }  // namespace offline_pages
 
 #endif  // COMPONENTS_OFFLINE_PAGES_OFFLINE_PAGE_MODEL_H_