Tiny change to make code match the comment.

src/handles.cc

 // Copyright 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 263 matching lines @@
 Handle<Object> GetHiddenProperties(Handle<JSObject> obj,
                                    bool create_if_needed) {
   Handle<String> key = Factory::hidden_symbol();
 
   if (obj->HasFastProperties()) {
     // If the object has fast properties, check whether the first slot
     // in the descriptor array matches the hidden symbol. Since the
     // hidden symbols hash code is zero (and no other string has hash
     // code zero) it will always occupy the first entry if present.
     DescriptorArray* descriptors = obj->map()->instance_descriptors();
-    DescriptorReader r(descriptors);
+    DescriptorReader r(descriptors, 0);  // Explicitly position reader at zero.
     if (!r.eos() && (r.GetKey() == *key) && r.IsProperty()) {
       ASSERT(r.type() == FIELD);
       return Handle<Object>(obj->FastPropertyAt(r.GetFieldIndex()));
     }
   }
 
   // Only attempt to find the hidden properties in the local object and not
   // in the prototype chain.  Note that HasLocalProperty() can cause a GC in
   // the general case in the presence of interceptors.
   if (!obj->HasLocalProperty(*key)) {
@@ skipping 436 matching lines @@
   Handle<Map> new_map = Factory::CopyMapDropTransitions(old_map);
   obj->set_map(*new_map);
   new_map->set_needs_loading(true);
   // Store the lazy loading info in the constructor field.  We'll
   // reestablish the constructor from the fixed array after loading.
   new_map->set_constructor(*arr);
   ASSERT(!obj->IsLoaded());
 }
 
 } }  // namespace v8::internal