internal PropertyDescriptor AddOwnProperty(DObject obj, string field, int fieldId, PropertyDescriptor.Attributes attributes)
{
PropertyMap newMap = AddOwnProperty(field, fieldId, attributes);
obj.Map = newMap;
var mapMetadata = Metadata.GetMapMetadataOfPrototype(obj, false);
if (mapMetadata != null)
{
mapMetadata.PropagateAdditionDownPrototypeChain(obj, newMap.Property); //obj is some other objects' prototype
}
return(newMap.Property);
}