Add more missing closing namespace comments.

third_party/WebKit/Source/core/svg/SVGTextPositioningElement.cpp

 /*
  * Copyright (C) 2004, 2005, 2008 Nikolas Zimmermann <zimmermann@kde.org>
  * Copyright (C) 2004, 2005, 2006, 2007, 2008 Rob Buis <buis@kde.org>
  *
  * 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,
@@ skipping 72 matching lines @@
     if (!layoutObject.isSVGText() && !layoutObject.isSVGInline())
         return nullptr;
 
     Node* node = layoutObject.node();
     ASSERT(node);
     ASSERT(node->isSVGElement());
 
     return isSVGTextPositioningElement(*node) ? toSVGTextPositioningElement(node) : 0;
 }
 
-}
+} // namespace blink