Special submit handling.
Overrides QueryPluginBase::submitOptionsForm
public function submitOptionsForm(&$form, &$form_state) {
$element = array(
'#parents' => array(
'query',
'options',
'query_tags',
),
);
$value = explode(',', NestedArray::getValue($form_state['values'], $element['#parents']));
$value = array_filter(array_map('trim', $value));
form_set_value($element, $value, $form_state);
}