Wipe out offline page data on clearing cookie and site data

components/offline_pages/offline_page_metadata_store_impl.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_METADATA_STORE_IMPL_H_
 #define COMPONENTS_OFFLINE_PAGES_OFFLINE_PAGE_METADATA_STORE_IMPL_H_
 
 #include <vector>
 
+#include "base/files/file_path.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
 #include "components/leveldb_proto/proto_database.h"
 #include "components/offline_pages/offline_page_metadata_store.h"
 
 namespace base {
-class FilePath;
+class SequencedTaskRunner;
 }
 
 namespace offline_pages {
 
 class OfflinePageEntry;
 
 // Implements OfflinePageMetadataStore using leveldb_proto::ProtoDatabase
 // component. Stores metadata of offline pages as serialized protobufs in a
 // LevelDB key/value pairs.
 // Underlying implementation guarantees that all of the method calls will be
 // executed sequentially, and started operations will finish even after the
 // store is already destroyed (callbacks will be called).
 class OfflinePageMetadataStoreImpl : public OfflinePageMetadataStore {
  public:
   OfflinePageMetadataStoreImpl(
-      scoped_ptr<leveldb_proto::ProtoDatabase<OfflinePageEntry>> database,
+      scoped_refptr<base::SequencedTaskRunner> background_task_runner,
       const base::FilePath& database_dir);
   ~OfflinePageMetadataStoreImpl() override;
 
   // OfflinePageMetadataStore implementation:
   void Load(const LoadCallback& callback) override;
   void AddOrUpdateOfflinePage(const OfflinePageItem& offline_page_record,
                               const UpdateCallback& callback) override;
   void RemoveOfflinePages(const std::vector<int64>& bookmark_ids,
                           const UpdateCallback& callback) override;
+  void Reset(const ResetCallback& callback) override;
 
  private:
-  // Callback for when initialization of the |database_| is done.
-  void OnInitDone(bool success);
+  void LoadContinuation(const LoadCallback& callback, bool success);
+  void LoadCompleted(const LoadCallback& callback,
+                     bool success,
+                     scoped_ptr<std::vector<OfflinePageEntry>> entries);
 
   // Implements the update.
   void UpdateEntries(
       scoped_ptr<leveldb_proto::ProtoDatabase<OfflinePageEntry>::KeyEntryVector>
           entries_to_save,
       scoped_ptr<std::vector<std::string>> keys_to_remove,
       const UpdateCallback& callback);
+  void UpdateCompleted(
+      const OfflinePageMetadataStore::UpdateCallback& callback,
+      bool success);
 
-  // Resets the database. This is to be used when one of the operations fails
-  // with no good explanation.
-  void ResetDB();
+  void ResetCompleted(const ResetCallback& callback, bool success);
 
+  scoped_refptr<base::SequencedTaskRunner> background_task_runner_;
+  base::FilePath database_dir_;
   scoped_ptr<leveldb_proto::ProtoDatabase<OfflinePageEntry>> database_;
 
   base::WeakPtrFactory<OfflinePageMetadataStoreImpl> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(OfflinePageMetadataStoreImpl);
 };
 
 }  // namespace offline_pages
 
 #endif  // COMPONENTS_OFFLINE_PAGES_OFFLINE_PAGE_METADATA_STORE_IMPL_H_