First implementation of allocation elimination in Hydrogen.

src/zone.h

Index: src/zone.h
diff --git a/src/zone.h b/src/zone.h
index 6ed38d3a5626e0c5168c59345827f91209a9eeaf..bd7cc39b0c4f224b0646792fbd8ed262fdc5f986 100644
--- a/src/zone.h
+++ b/src/zone.h
@@ -202,7 +202,7 @@ class ZoneList: public List<T, ZoneAllocationPolicy> {
   ZoneList(const ZoneList<T>& other, Zone* zone)
       : List<T, ZoneAllocationPolicy>(other.length(),
                                       ZoneAllocationPolicy(zone)) {
-    AddAll(other, ZoneAllocationPolicy(zone));
+    AddAll(other, zone);
   }
 
   // We add some convenience wrappers so that we can pass in a Zone
@@ -210,8 +210,7 @@ class ZoneList: public List<T, ZoneAllocationPolicy> {
   INLINE(void Add(const T& element, Zone* zone)) {
     List<T, ZoneAllocationPolicy>::Add(element, ZoneAllocationPolicy(zone));
   }
-  INLINE(void AddAll(const List<T, ZoneAllocationPolicy>& other,
-                     Zone* zone)) {
+  INLINE(void AddAll(const List<T, ZoneAllocationPolicy>& other, Zone* zone)) {
     List<T, ZoneAllocationPolicy>::AddAll(other, ZoneAllocationPolicy(zone));
   }
   INLINE(void AddAll(const Vector<T>& other, Zone* zone)) {