Add more missing closing namespace comments.

third_party/WebKit/Source/core/xml/XPathVariableReference.h

 /*
  * Copyright 2005 Frerich Raabe <raabe@kde.org>
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
@@ skipping 26 matching lines @@
 public:
     explicit VariableReference(const String& name);
 
 private:
     Value evaluate(EvaluationContext&) const override;
     Value::Type resultType() const override { ASSERT_NOT_REACHED(); return Value::NumberValue; }
 
     String m_name;
 };
 
-}
+} // namespace XPath
 
-}
+} // namespace blink
 #endif // XPathVariableReference_h