Oilpan: reduce visibility of Visitor::trace(const RawPtr<T>&).

Source/heap/Visitor.h

 /*
  * Copyright (C) 2013 Google 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 301 matching lines @@
     // Remove this once we remove RefPtrWillBeMember.
     template<typename T>
     void trace(const RefPtr<T>&)
     {
 #if ENABLE(OILPAN)
         // RefPtrs should never be traced.
         ASSERT_NOT_REACHED();
 #endif
     }
 
+#if !ENABLE(OILPAN)
     // Similarly, this trace method is to trace a RawPtrWillBeMember
     // when ENABLE(OILPAN) is not enabled.
     // Remove this once we remove RawPtrWillBeMember.
     template<typename T>
     void trace(const RawPtr<T>&)
     {
-#if ENABLE(OILPAN)
-        // RawPtrs should never be traced.
-        ASSERT_NOT_REACHED();
+    }
 #endif
-    }
 
     // This method marks an object and adds it to the set of objects
     // that should have their trace method called. Since not all
     // objects have vtables we have to have the callback as an
     // explicit argument, but we can use the templated one-argument
     // mark method above to automatically provide the callback
     // function.
     virtual void mark(const void*, TraceCallback) = 0;
 
     // Used to mark objects during conservative scanning.
@@ skipping 200 matching lines @@
     return visitor->isMarked(obj);
 }
 template<typename T> bool ObjectAliveTrait<Member<T> >::isAlive(Visitor* visitor, const Member<T>& obj)
 {
     return visitor->isMarked(obj.get());
 }
 
 }
 
 #endif