[Sync] Add SyncEncryptionHandler

chrome/browser/sync/glue/nigori_change_processor.h

+// Copyright (c) 2012 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_GLUE_NIGORI_CHANGE_PROCESSOR_H_
+#define CHROME_BROWSER_SYNC_GLUE_NIGORI_CHANGE_PROCESSOR_H_
+
+#include "sync/internal_api/public/base/model_type.h"
+
+namespace syncer {
+struct Experiments;
+class SyncEncryptionHandler;
+struct UserShare;
+}
+
+namespace browser_sync {
+
+// A change processor for handling updates to the nigori node. Interacts
+// directly with the SyncEncryptionHandler.
+// TODO(zea): implement the ChangeProcessor interface.
+class NigoriChangeProcessor {
+ public:
+  NigoriChangeProcessor(
+      syncer::SyncEncryptionHandler* encryption_handler);
+  virtual ~NigoriChangeProcessor();
+
+  // Merge local state and nigori node state.
+  void AssociateModels(syncer::UserShare* user_share);
+  // Disconnect the change processor from sync.
+  void DisassociateModels();
+
+  // Reads the nigori node to determine if any experimental features should
+  // be enabled.
+  // Note: opens a transaction.  May be called on any thread.
+  bool ReceivedExperiments(syncer::Experiments* experiments);
+
+  // TODO(zea): ChangeProcessor implementation.
+ private:
+  DISALLOW_COPY_AND_ASSIGN(NigoriChangeProcessor);
+
+  // This profile's user share. Used to create sync transactions.
+  syncer::UserShare* user_share_;
+
+  // Sync's encryption handler.
+  syncer::SyncEncryptionHandler* encryption_handler_;
+};
+
+}  // namespace browser_sync
+
+#endif  // CHROME_BROWSER_SYNC_GLUE_NIGORI_CHANGE_PROCESSOR_H_