set_owner_attributes

# File activerecord/lib/active_record/associations/foreign_association.rb, line 22
      def set_owner_attributes(record)
        return if options[:through]

        key = owner._read_attribute(reflection.join_foreign_key)
        record._write_attribute(reflection.join_primary_key, key)

        if reflection.type
          record._write_attribute(reflection.type, owner.class.polymorphic_name)
        end
      end