Remove ENABLE(OILPAN) uses in wtf/

third_party/WebKit/Source/wtf/HashSet.h

 /*
  * Copyright (C) 2005, 2006, 2007, 2008, 2011 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 253 matching lines @@
         typename W::GCForbiddenScope scope;
         vector.resize(collection.size());
     }
 
     iterator it = collection.begin();
     iterator end = collection.end();
     for (unsigned i = 0; it != end; ++it, ++i)
         vector[i] = *it;
 }
 
-#if !ENABLE(OILPAN)
-template <typename T, typename U, typename V>
-struct NeedsTracing<HashSet<T, U, V>> {
-    static const bool value = false;
-};
-#endif
-
 } // namespace WTF
 
 using WTF::HashSet;
 
 #endif // WTF_HashSet_h