composite key's multiple in's with nulls

#3408 fix for having $columnName an array and multiple values ($n>1).
IE:
Yii::app()->db->getSchema()->getCommandBuilder()->createInCondition('test',array('id', 'color'),array(
	array('id' => 11, 'color' => ''),
	array('id' => 8, 'color' => null),
	array('id' => null, 'color' => 'test'),
));