Time without date won't get validated, when kDateFormatter is used

In case if you have field, that is defined using mentioned above code, then it's never gonna be validated (combination of input_date_format and required options) - HeatingTime_date field will always be empty and of course required.

'Fields' => Array(
'HeatingTime' => Array (
'type' => 'int',
'formatter' => 'kDateFormatter', 'date_format' => '', 'input_date_format' => '', 'time_format' => 'i:s', 'input_time_format' => 'i:s',
'required' => 1,
),
),