Exposed filter elements do not have aria-describedby attributes

This problem was found by my accessibility reviewer today on a new site. I need to update the version so I can fork off 11.x.

Until this issue is patched, I'll be using the following code to work around it:

function MYMODULE_preprocess_input__form_control__textfield(&$variables) {
  $element = $variables['element'];
  if (isset($element['#description']) && !isset($element['#attributes']['aria-describedby'])) {
    $description_id = $element['#id'] . '--description';
    $variables['attributes']->setAttribute('aria-describedby', $description_id);
  }
}