Progress towards making Zones independent of Isolates and Threads.

src/zone-inl.h

 // Copyright 2012 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 72 matching lines @@
   segment_bytes_allocated_ += delta;
   isolate_->counters()->zone_segment_bytes()->Set(segment_bytes_allocated_);
 }
 
 
 template <typename Config>
 ZoneSplayTree<Config>::~ZoneSplayTree() {
   // Reset the root to avoid unneeded iteration over all tree nodes
   // in the destructor.  For a zone-allocated tree, nodes will be
   // freed by the Zone.
-  SplayTree<Config, ZoneListAllocationPolicy>::ResetRoot();
+  SplayTree<Config, ZoneAllocationPolicy>::ResetRoot();
 }
 
 
 // TODO(isolates): for performance reasons, this should be replaced with a new
 //                 operator that takes the zone in which the object should be
 //                 allocated.
 void* ZoneObject::operator new(size_t size) {
   return ZONE->New(static_cast<int>(size));
 }
 
 void* ZoneObject::operator new(size_t size, Zone* zone) {
   return zone->New(static_cast<int>(size));
 }
 
-
-inline void* ZoneListAllocationPolicy::New(int size) {
-  return ZONE->New(size);
+inline void* ZoneAllocationPolicy::New(size_t size) {
+  if (zone_) {
+    return zone_->New(size);
+  } else {
+    return ZONE->New(size);
+  }
 }
 
 
 template <typename T>
 void* ZoneList<T>::operator new(size_t size) {
   return ZONE->New(static_cast<int>(size));
 }
 
 
 template <typename T>
@@ skipping 14 matching lines @@
 
 
 int ZoneScope::nesting() {
   return Isolate::Current()->zone()->scope_nesting_;
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_ZONE_INL_H_