Validate the options form.
Overrides PluginBase::validateOptionsForm
public function validateOptionsForm(&$form, &$form_state) {
// Don't run validation on style plugins without the grouping setting.
if (isset($form_state['values']['style_options']['grouping'])) {
// Don't save grouping if no field is specified.
foreach ($form_state['values']['style_options']['grouping'] as $index => $grouping) {
if (empty($grouping['field'])) {
unset($form_state['values']['style_options']['grouping'][$index]);
}
}
}
}