[USS] TypedURLSyncMetadataDatabase inherits SyncMetadataStores

components/history/core/browser/typed_url_sync_metadata_database.h

 // Copyright 2017 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_HISTORY_CORE_BROWSER_TYPED_URL_SYNC_METADATA_DATABASE_H_
 #define COMPONENTS_HISTORY_CORE_BROWSER_TYPED_URL_SYNC_METADATA_DATABASE_H_
 
 #include "base/macros.h"
 #include "components/sync/base/model_type.h"
 #include "components/sync/model/metadata_batch.h"
+#include "components/sync/model/sync_metadata_store.h"
 #include "sql/meta_table.h"
 
 namespace sql {
 class Connection;
 }
 
 namespace history {
 
 // A sync metadata database needs to maintain two tables: entity metadata table
 // and datatype state table. Entity metadata table contains metadata(sync
 // states) for each url. Datatype state table contains the state of typed url
 // datatype.
-class TypedURLSyncMetadataDatabase {
+class TypedURLSyncMetadataDatabase : public syncer::SyncMetadataStore {
  public:
   // Must call InitVisitTable() before using to make sure the database is
   // initialized.
   TypedURLSyncMetadataDatabase();
-  virtual ~TypedURLSyncMetadataDatabase();
+  ~TypedURLSyncMetadataDatabase() override;
 
   // Read all the stored metadata for typed URL and fill |metadata_batch|
   // with it.
   bool GetAllSyncMetadata(syncer::MetadataBatch* metadata_batch);
 
-  // Update the metadata row for typed URL, keyed by |storage_key|, to
-  // contain the contents of |metadata|.
-  bool UpdateSyncMetadata(const std::string& storage_key,
-                          const sync_pb::EntityMetadata& metadata);
-
-  // Remove the metadata row of typed URL keyed by |storage_key|.
-  bool ClearSyncMetadata(const std::string& storage_key);
-
-  // Update the stored sync state for the typed URL.
-  bool UpdateModelTypeState(const sync_pb::ModelTypeState& model_type_state);
-
-  // Clear the stored sync state for typed URL.
-  bool ClearModelTypeState();
+  // syncer::SyncMetadataStore implementation.
+  bool UpdateSyncMetadata(syncer::ModelType model_type,
+                          const std::string& storage_key,
+                          const sync_pb::EntityMetadata& metadata) override;
+  bool ClearSyncMetadata(syncer::ModelType model_type,
+                         const std::string& storage_key) override;
+  bool UpdateModelTypeState(
+      syncer::ModelType model_type,
+      const sync_pb::ModelTypeState& model_type_state) override;
+  bool ClearModelTypeState(syncer::ModelType model_type) override;
 
  protected:
   // Returns the database for the functions in this interface.
   virtual sql::Connection& GetDB() = 0;
 
   // Returns MetaTable, so this sync can store ModelTypeState in MetaTable.
   // Check if GetMetaTable().GetVersionNumber() is greater than 0 to make sure
   // MetaTable is initialed.
   virtual sql::MetaTable& GetMetaTable() = 0;
 
   // Called by the derived classes on initialization to make sure the tables
   // and indices are properly set up. Must be called before anything else.
   bool InitSyncTable();
 
  private:
   // Read all sync_pb::EntityMetadata for typed URL and fill
   // |metadata_records| with it.
   bool GetAllSyncEntityMetadata(syncer::MetadataBatch* metadata_batch);
 
   // Read sync_pb::ModelTypeState for typed URL and fill |state| with it.
   bool GetModelTypeState(sync_pb::ModelTypeState* state);
 
   DISALLOW_COPY_AND_ASSIGN(TypedURLSyncMetadataDatabase);
 };
 
 }  // namespace history
 
 #endif  // COMPONENTS_HISTORY_CORE_BROWSER_TYPED_URL_SYNC_METADATA_DATABASE_H_