Have VisitorHelper<> handle moving object registration.

third_party/WebKit/Source/platform/heap/SparseHeapBitmap.cpp

 // Copyright 2016 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/heap/SparseHeapBitmap.h"
 
+#include "platform/heap/Heap.h"
 #include "wtf/PtrUtil.h"
 
 namespace blink {
 
 // Return the subtree/bitmap that covers the
 // [address, address + size) range.  Null if there is none.
 SparseHeapBitmap* SparseHeapBitmap::hasRange(Address address, size_t size) {
   DCHECK(!(reinterpret_cast<uintptr_t>(address) & s_pointerAlignmentMask));
   SparseHeapBitmap* bitmap = this;
   while (bitmap) {
@@ skipping 85 matching lines @@
 size_t SparseHeapBitmap::intervalCount() const {
   size_t count = 1;
   if (m_left)
     count += m_left->intervalCount();
   if (m_right)
     count += m_right->intervalCount();
   return count;
 }
 
 }  // namespace blink