Add more missing closing namespace comments.

third_party/WebKit/Source/core/html/forms/RadioButtonGroupScope.cpp

 /*
  * Copyright (C) 2007, 2008, 2009 Apple Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ skipping 263 matching lines @@
     }
 }
 
 DEFINE_TRACE(RadioButtonGroupScope)
 {
 #if ENABLE(OILPAN)
     visitor->trace(m_nameToGroupMap);
 #endif
 }
 
-} // namespace
+} // namespace blink