Implement new SyncAPI and convert Preferences to it.

chrome/browser/sync/api/syncable_service.h

+// Copyright (c) 2011 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 CHROME_BROWSER_SYNC_API_SYNCABLE_SERVICE_H_
+#define CHROME_BROWSER_SYNC_API_SYNCABLE_SERVICE_H_
+#pragma once
+
+#include <vector>
+
+#include "chrome/browser/sync/syncable/model_type.h"
+#include "chrome/browser/sync/api/sync_change_processor.h"
+#include "chrome/browser/sync/api/sync_data.h"
+
+class SyncData;
+
+typedef std::vector<SyncData> SyncDataList;
+
+class SyncableService : public SyncChangeProcessor {
+ public:
+  // Informs the service to begin syncing the specified synced datatype |type|.
+  // The service should then merge |initial_sync_data| into it's local data,
+  // calling |sync_processor|'s ProcessSyncChanges as necessary to reconcile the
+  // two. After this, the SyncableService's local data should match the server
+  // data, and the service should be ready to receive and process any further
+  // SyncChange's as they occur.
+  virtual bool MergeDataAndStartSyncing(
+      syncable::ModelType type,
+      const SyncDataList& initial_sync_data,
+      SyncChangeProcessor* sync_processor) = 0;
+
+  // Stop syncing the specified type and reset state.
+  virtual void StopSyncing(syncable::ModelType type) = 0;
+
+  // Fills a list of SyncData from the local data. This should create an up
+  // to date representation of the SyncableService's view of that datatype, and
+  // should match/be a subset of the server's view of that datatype.
+  virtual SyncDataList GetAllSyncData(syncable::ModelType type) const = 0;
+
+  // SyncChangeProcessor interface.
+  // Process a list of new SyncChanges and update the local data as necessary.
+  virtual void ProcessSyncChanges(const SyncChangeList& change_list) = 0;
+
+ protected:
+  virtual ~SyncableService();
+};
+
+#endif  // CHROME_BROWSER_SYNC_API_SYNCABLE_SERVICE_H_