Limited the size of transition arrays so they never end up in the large object space.

src/objects-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 3564 matching lines @@
 bool Map::HasTransitionArray() {
   return instance_descriptors()->HasTransitionArray();
 }
 
 
 Map* Map::elements_transition_map() {
   return transitions()->elements_transition();
 }
 
 
+bool Map::CanHaveMoreTransitions() {
+  if (!HasTransitionArray()) return true;
+  return FixedArray::SizeFor(transitions()->length() +
+                             TransitionArray::kTransitionSize)
+      <= Page::kMaxNonCodeHeapObjectSize;
+}
+
+
 MaybeObject* Map::AddTransition(String* key, Map* target) {
   if (HasTransitionArray()) return transitions()->CopyInsert(key, target);
   return TransitionArray::NewWith(key, target);
 }
 
 
 void Map::SetTransition(int transition_index, Map* target) {
   transitions()->SetTarget(transition_index, target);
 }
 
@@ skipping 1787 matching lines @@
 #undef WRITE_UINT32_FIELD
 #undef READ_SHORT_FIELD
 #undef WRITE_SHORT_FIELD
 #undef READ_BYTE_FIELD
 #undef WRITE_BYTE_FIELD
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_OBJECTS_INL_H_