Property reconfiguring implemented. Tests added.

src/lookup.cc

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/v8.h"
 
 #include "src/bootstrapper.h"
 #include "src/deoptimizer.h"
 #include "src/lookup.h"
 #include "src/lookup-inl.h"
@@ skipping 87 matching lines @@
 
 void LookupIterator::ReconfigureDataProperty(Handle<Object> value,
                                              PropertyAttributes attributes) {
   DCHECK(state_ == DATA || state_ == ACCESSOR);
   DCHECK(HolderIsReceiverOrHiddenPrototype());
   Handle<JSObject> holder = GetHolder<JSObject>();
   if (holder_map_->is_dictionary_map()) {
     PropertyDetails details(attributes, v8::internal::DATA, 0);
     JSObject::SetNormalizedProperty(holder, name(), value, details);
   } else {
-    holder_map_ = Map::ReconfigureDataProperty(holder_map_, descriptor_number(),
-                                               attributes);
+    holder_map_ = Map::ReconfigureExistingProperty(
+        holder_map_, descriptor_number(), i::kData, attributes);
+    holder_map_ =
+        Map::PrepareForDataProperty(holder_map_, descriptor_number(), value);
     JSObject::MigrateToMap(holder, holder_map_);
   }
 
   ReloadPropertyInformation();
 }
 
 
 void LookupIterator::PrepareTransitionToDataProperty(
     Handle<Object> value, PropertyAttributes attributes,
     Object::StoreFromKeyed store_mode) {
@@ skipping 231 matching lines @@
   }
   return false;
 }
 
 
 void LookupIterator::InternalizeName() {
   if (name_->IsUniqueName()) return;
   name_ = factory()->InternalizeString(Handle<String>::cast(name_));
 }
 } }  // namespace v8::internal