Add more missing closing namespace comments.

third_party/WebKit/Source/platform/graphics/PaintInvalidationReason.cpp

 // Copyright 2014 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 "platform/graphics/PaintInvalidationReason.h"
 
 #include "wtf/Assertions.h"
 
 namespace blink {
 
@@ skipping 44 matching lines @@
         return "layoutObject removal";
     case PaintInvalidationSVGResourceChange:
         return "SVG resource change";
     case PaintInvalidationDelayedFull:
         return "delayed full";
     }
     ASSERT_NOT_REACHED();
     return "";
 }
 
-}
+} // namespace blink