Have VisitorHelper<> handle moving object registration.

third_party/WebKit/Source/platform/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 265 matching lines @@
     registerWeakMembers(obj, &TraceMethodDelegate<T, method>::trampoline);
   }
 
   void registerWeakMembers(const void* object, WeakCallback callback) {
     Derived::fromHelper(this)->registerWeakMembers(object, object, callback);
   }
 
   void registerBackingStoreReference(void* slot) {
     if (getMarkingMode() != VisitorMarkingMode::GlobalMarkingWithCompaction)
       return;
-    Derived::fromHelper(this)->registerMovingObjectReference(
+    heap().registerMovingObjectReference(
         reinterpret_cast<MovableReference*>(slot));
   }
 
   void registerBackingStoreCallback(void* backingStore,
                                     MovingObjectCallback callback,
                                     void* callbackData) {
     if (getMarkingMode() != VisitorMarkingMode::GlobalMarkingWithCompaction)
       return;
-    Derived::fromHelper(this)->registerMovingObjectCallback(
+    heap().registerMovingObjectCallback(
         reinterpret_cast<MovableReference>(backingStore), callback,
         callbackData);
   }
 
   inline ThreadState* state() const { return m_state; }
   inline ThreadHeap& heap() const { return state()->heap(); }
 
   inline VisitorMarkingMode getMarkingMode() const { return m_markingMode; }
 
   inline bool isGlobalMarking() const {
@@ skipping 74 matching lines @@
 
   virtual void registerWeakTable(const void*,
                                  EphemeronCallback,
                                  EphemeronCallback) = 0;
 #if DCHECK_IS_ON()
   virtual bool weakTableRegistered(const void*) = 0;
 #endif
 
   virtual bool ensureMarked(const void*) = 0;
 
-  virtual void registerMovingObjectReference(MovableReference*) = 0;
-
-  virtual void registerMovingObjectCallback(MovableReference,
-                                            MovingObjectCallback,
-                                            void*) = 0;
-
   virtual void registerWeakCellWithCallback(void**, WeakCallback) = 0;
 
  protected:
   Visitor(ThreadState*, VisitorMarkingMode);
 
  private:
   static Visitor* fromHelper(VisitorHelper<Visitor>* helper) {
     return static_cast<Visitor*>(helper);
   }
 };
 
 }  // namespace blink
 
 #endif  // Visitor_h