Get rid of the ZoneScopeMode.

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 92 matching lines @@
   return zone_->New(static_cast<int>(size));
 }
 
 
 template <typename T>
 void* ZoneList<T>::operator new(size_t size, Zone* zone) {
   return zone->New(static_cast<int>(size));
 }
 
 
-ZoneScope::ZoneScope(Zone* zone, ZoneScopeMode mode)
-    : zone_(zone), mode_(mode) {
+ZoneScope::ZoneScope(Zone* zone)
+    : zone_(zone) {
   zone_->scope_nesting_++;
 }
 
 
 bool ZoneScope::ShouldDeleteOnExit() {
-  return zone_->scope_nesting_ == 1 && mode_ == DELETE_ON_EXIT;
+  return zone_->scope_nesting_ == 1;
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_ZONE_INL_H_