Add more missing closing namespace comments.

third_party/WebKit/Source/core/dom/NodeWithIndex.h

 /*
  * Copyright (C) 2008 Apple Inc. All Rights Reserved.
  *
  * 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
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 42 matching lines @@
         return m_index;
     }
 
 private:
     bool hasIndex() const { return m_index >= 0; }
 
     RawPtrWillBeMember<Node> m_node;
     mutable int m_index;
 };
 
-}
+} // namespace blink
 
 #endif