[Sync] Move ModelType and related classes to 'syncer' namespace

sync/engine/syncproto.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.
 //
 // Wrappers to help us work with ids and protobuffers.
 
 #ifndef SYNC_ENGINE_SYNCPROTO_H_
 #define SYNC_ENGINE_SYNCPROTO_H_
 #pragma once
 
@@ skipping 42 matching lines @@
   }
   // Binary predicate helper to determine whether an Entity represents a folder
   // or non-folder object. Use this instead of checking these properties
   // directly, because the addition of bookmarks to the protobuf schema
   // makes the check slightly more tricky.
   bool IsFolder() const {
     return ((has_folder() && folder()) ||
             (has_bookmarkdata() && bookmarkdata().bookmark_folder()));
   }
 
-  syncable::ModelType GetModelType() const {
-    return syncable::GetModelType(*this);
+  syncer::ModelType GetModelType() const {
+    return syncer::GetModelType(*this);
   }
 };
 
 class CommitResponse_EntryResponse
     : public IdWrapper<sync_pb::CommitResponse_EntryResponse> {
 };
 
 class ClientToServerMessage : public sync_pb::ClientToServerMessage {
  public:
   ClientToServerMessage() {
     set_protocol_version(protocol_version());
   }
 };
 
 typedef sync_pb::CommitMessage CommitMessage;
 typedef sync_pb::ClientToServerResponse ClientToServerResponse;
 typedef sync_pb::CommitResponse CommitResponse;
 typedef sync_pb::GetUpdatesResponse GetUpdatesResponse;
 typedef sync_pb::GetUpdatesMessage GetUpdatesMessage;
 
 }  // namespace syncer
 
 #endif  // SYNC_ENGINE_SYNCPROTO_H_