update_with_timestamps

# File activerecord/lib/active_record/timestamp.rb, line 32
      def update_with_timestamps(*args) #:nodoc:
        if record_timestamps && (!partial_updates? || changed?)
          t = self.class.default_timezone == :utc ? Time.now.utc : Time.now
          write_attribute('updated_at', t) if respond_to?(:updated_at)
          write_attribute('updated_on', t) if respond_to?(:updated_on)
        end
        update_without_timestamps(*args)
      end