Let the second pass phantom callbacks run in a separate task on the foreground thread.

src/list-inl.h

 // Copyright 2006-2009 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_LIST_INL_H_
 #define V8_LIST_INL_H_
 
 #include "src/list.h"
 
 #include "src/base/macros.h"
@@ skipping 107 matching lines @@
 bool List<T, P>::RemoveElement(const T& elm) {
   for (int i = 0; i < length_; i++) {
     if (data_[i] == elm) {
       Remove(i);
       return true;
     }
   }
   return false;
 }
 
+template <typename T, class P>
+void List<T, P>::Swap(List<T, P>* list) {
+  std::swap(data_, list->data_);
+  std::swap(length_, list->length_);
+  std::swap(capacity_, list->capacity_);
+}
 
 template<typename T, class P>
 void List<T, P>::Allocate(int length, P allocator) {
   DeleteData(data_);
   Initialize(length, allocator);
   length_ = length;
 }
 
 
 template<typename T, class P>
@@ skipping 147 matching lines @@
 
 template <typename T>
 int SortedListBSearch(const List<T>& list, T elem) {
   return SortedListBSearch<T, ElementCmp<T> > (list, ElementCmp<T>(elem));
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_LIST_INL_H_