[Sync] Add ability to save/restore Nigori to SyncEncryptionHandlerImpl

sync/internal_api/js_sync_encryption_handler_observer.h

 // Copyright 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 SYNC_INTERNAL_API_JS_SYNC_ENCRYPTION_HANDLER_OBSERVER_H_
 #define SYNC_INTERNAL_API_JS_SYNC_ENCRYPTION_HANDLER_OBSERVER_H_
 
 #include <string>
 
 #include "base/basictypes.h"
@@ skipping 27 matching lines @@
       const sync_pb::EncryptedData& pending_keys) override;
   void OnPassphraseAccepted() override;
   void OnBootstrapTokenUpdated(const std::string& bootstrap_token,
                                BootstrapTokenType type) override;
   void OnEncryptedTypesChanged(ModelTypeSet encrypted_types,
                                bool encrypt_everything) override;
   void OnEncryptionComplete() override;
   void OnCryptographerStateChanged(Cryptographer* cryptographer) override;
   void OnPassphraseTypeChanged(PassphraseType type,
                                base::Time explicit_passphrase_time) override;
+  void OnLocalSetCustomPassphrase(
+      const SyncEncryptionHandler::NigoriState& nigori_state) override;
 
  private:
   void HandleJsEvent(const tracked_objects::Location& from_here,
                     const std::string& name, const JsEventDetails& details);
 
   WeakHandle<JsEventHandler> event_handler_;
 
   DISALLOW_COPY_AND_ASSIGN(JsSyncEncryptionHandlerObserver);
 };
 
 }  // namespace syncer
 
 #endif  // SYNC_INTERNAL_API_JS_SYNC_ENCRYPTION_HANDLER_OBSERVER_H_