FYI: Control Data + Per-Device Metadata

sync/internal_api/public/engine/control_model_worker.cc

Index: sync/internal_api/public/engine/control_model_worker.cc
diff --git a/sync/internal_api/public/engine/control_model_worker.cc b/sync/internal_api/public/engine/control_model_worker.cc
new file mode 100644
index 0000000000000000000000000000000000000000..78f848c944467144d46538ff08167083c3050dd6
--- /dev/null
+++ b/sync/internal_api/public/engine/control_model_worker.cc
@@ -0,0 +1,29 @@
+// 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.
+
+#include "sync/internal_api/public/engine/control_model_worker.h"
+
+#include "base/message_loop.h"
+
+namespace syncer {
+
+ControlModelWorker::ControlModelWorker(const MessageLoop* sync_loop)
+    : sync_loop_(sync_loop) {}
+
+ControlModelWorker::~ControlModelWorker() {
+}
+
+SyncerError ControlModelWorker::DoWorkAndWaitUntilDone(
+    const WorkCallback& work) {
+  DCHECK_EQ(MessageLoop::current(), sync_loop_);
+  // Simply do the work on the current thread.
+  return work.Run();
+}
+
+ModelSafeGroup ControlModelWorker::GetModelSafeGroup() {
+  return GROUP_CONTROL;
+}
+
+}  // namespace syncer
+