Grow lists by a factor of 2 instead of 1.5 on a resize.

src/list-inl.h

 // Copyright 2006-2009 the V8 project authors. 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
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 54 matching lines @@
 // use the same implementation as the inlined version.
 template<typename T, class P>
 void List<T, P>::ResizeAdd(const T& element) {
   ResizeAddInternal(element);
 }
 
 
 template<typename T, class P>
 void List<T, P>::ResizeAddInternal(const T& element) {
   ASSERT(length_ >= capacity_);
-  // Grow the list capacity by 50%, but make sure to let it grow
+  // Grow the list capacity by 100%, but make sure to let it grow
   // even when the capacity is zero (possible initial case).
-  int new_capacity = 1 + capacity_ + (capacity_ >> 1);
+  int new_capacity = 1 + 2 * capacity_;
   // Since the element reference could be an element of the list, copy
   // it out of the old backing storage before resizing.
   T temp = element;
   Resize(new_capacity);
   data_[length_++] = temp;
 }
 
 
 template<typename T, class P>
 void List<T, P>::Resize(int new_capacity) {
@@ skipping 145 matching lines @@
 
 template <typename T>
 int SortedListBSearch(const List<T>& list, T elem) {
   return SortedListBSearch<T>(list, elem, PointerValueCompare<T>);
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_LIST_INL_H_