framework/data/DataFilter.php
public function __isset($name)
    {
        if ($name === $this->filterAttributeName) {
            return $this->getFilter() !== null;
        }

        return parent::__isset($name);
    }
public function __isset($name)
    {
        if ($name === $this->filterAttributeName) {
            return $this->getFilter() !== null;
        }

        return parent::__isset($name);
    }
{@inheritdoc}