trait BrokenHandlerTrait in Zircon Profile 8.0

trait BrokenHandlerTrait {

  /**
   * Returns this handlers name in the UI.
   *
   * @see \Drupal\views\Plugin\views\PluginBase::defineOptions().
   */
  public function adminLabel($short = FALSE) {
    return t('Broken/missing handler');
  }

  /**
   * The option definition for this handler.
   *
   * @see \Drupal\views\Plugin\views\PluginBase::defineOptions().
   */
  public function defineOptions() {
    return array();
  }

  /**
   * Ensure the main table for this handler is in the query. This is used
   * a lot.
   *
   * @see \Drupal\views\Plugin\views\HandlerBase::ensureMyTable().
   */
  public function ensureMyTable() {

    // No table to ensure.
  }

  /**
   * Modify the views query.
   */
  public function query($group_by = FALSE) {

    /* No query to run */
  }

  /**
   * Provides a form to edit options for this plugin.
   *
   * @see \Drupal\views\Plugin\views\PluginBase::defineOptions().
   */
  public function buildOptionsForm(&$form, FormStateInterface $form_state) {
    $description_top = t('The handler for this item is broken or missing. The following details are available:');
    foreach ($this->definition['original_configuration'] as $key => $value) {
      if (is_scalar($value)) {
        $items[] = SafeMarkup::format('@key: @value', array(
          '@key' => $key,
          '@value' => $value,
        ));
      }
    }
    $description_bottom = t('Enabling the appropriate module will may solve this issue. Otherwise, check to see if there is a module update available.');
    $form['description'] = array(
      '#type' => 'container',
      '#attributes' => array(
        'class' => array(
          'js-form-item',
          'form-item',
          'description',
        ),
      ),
      'description_top' => array(
        '#markup' => '<p>' . $description_top . '</p>',
      ),
      'detail_list' => array(
        '#theme' => 'item_list',
        '#items' => $items,
      ),
      'description_bottom' => array(
        '#markup' => '<p>' . $description_bottom . '</p>',
      ),
    );
  }

  /**
   * Determines if the handler is considered 'broken'.
   *
   * This means it's a placeholder used when a handler can't be found.
   *
   * @see \Drupal\views\Plugin\views\HandlerBase::broken().
   */
  public function broken() {
    return TRUE;
  }

  /**
   * Gets dependencies for a broken handler.
   *
   * @return array
   *
   * @see \Drupal\views\Plugin\views\PluginBase::calculateDependencies().
   */
  public function calculateDependencies() {
    return [];
  }

}