Remove HasInlinedTraceMethod<T>.

Source/wtf/HashCountedSet.h

 /*
  * Copyright (C) 2005, 2006, 2008 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 62 matching lines @@
         bool remove(const ValueType& value) { return remove(find(value)); }
         bool remove(iterator);
 
         // Removes the value, regardless of its count.
         void removeAll(const ValueType& value) { removeAll(find(value)); }
         void removeAll(iterator);
 
         // Clears the whole set.
         void clear() { m_impl.clear(); }
 
-        using HasInlinedTraceMethodMarker = int;
         template<typename VisitorDispatcher>
         void trace(VisitorDispatcher visitor) { m_impl.trace(visitor); }
 
     private:
         ImplType m_impl;
     };
 
     template<typename T, typename U, typename V, typename W>
     inline typename HashCountedSet<T, U, V, W>::AddResult HashCountedSet<T, U, V, W>::add(const ValueType& value)
     {
@@ skipping 60 matching lines @@
     struct NeedsTracing<HashCountedSet<T, U, V>> {
         static const bool value = false;
     };
 #endif
 
 } // namespace WTF
 
 using WTF::HashCountedSet;
 
 #endif /* WTF_HashCountedSet_h */