Move NotificationDelegate into message_center.

ui/message_center/notification_delegate.cc

Index: ui/message_center/notification_delegate.cc
diff --git a/ui/message_center/notification_delegate.cc b/ui/message_center/notification_delegate.cc
new file mode 100644
index 0000000000000000000000000000000000000000..979b1be8fd59f19424fe2a9cfb08ab7389fcec17
--- /dev/null
+++ b/ui/message_center/notification_delegate.cc
@@ -0,0 +1,13 @@
+// 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 "ui/message_center/notification_delegate.h"
+
+namespace message_center {
+
+bool NotificationDelegate::HasClickedListener() { return false; }
+
+void NotificationDelegate::ButtonClick(int button_index) {}
+
+}  // namespace message_center