Views query settings error for multi-index search

With a "Multi-index search" view when clicking "Query settings: Settings" it gives the following error:

Error: Call to a member function getEntityType() on null in SearchApiViewsQuery->options_form() (line 216 of search_api/contrib/search_api_views/includes/query.inc).

Can be worked-around by doing:

search_api/contrib/search_api_views/includes/query.inc

  public function options_form(&$form, &$form_state) {
    ...
-   if ($this->index->getEntityType()) {
+   if ($this->index && $this->index->getEntityType()) {
      $form['entity_access'] = array(
        '#type' => 'checkbox',
        '#title' => t('Additional access checks on result entities'),
        '#description' => t("Execute an access check for all <snip>"),
        '#default_value' => $this->options['entity_access'],
      );
    }
    ...
  }