class LinkDelete

1. 8.x drupal/core/modules/shortcut/lib/Drupal/shortcut/Form/LinkDelete.php \Drupal\shortcut\Form\LinkDelete
2. 8.x drupal/core/modules/node/lib/Drupal/node/Plugin/views/field/LinkDelete.php \Drupal\node\Plugin\views\field\LinkDelete
3. 8.x drupal/core/modules/comment/lib/Drupal/comment/Plugin/views/field/LinkDelete.php \Drupal\comment\Plugin\views\field\LinkDelete

shortcut.routing.yml in drupal/core/modules/shortcut/shortcut.routing.yml

drupal/core/modules/shortcut/shortcut.routing.yml

class LinkDelete extends ConfirmFormBase {

  /**
   * The menu link to delete.
   *
   * @var \Drupal\menu_link\Plugin\Core\Entity\MenuLink
   */
  protected $menuLink;

  /**
   * {@inheritdoc}
   */
  public function getFormID() {
    return 'shortcut_link_delete';
  }

  /**
   * {@inheritdoc}
   */
  protected function getQuestion() {
    return t('Are you sure you want to delete the shortcut %title?', array(
      '%title' => $this->menuLink->link_title,
    ));
  }

  /**
   * {@inheritdoc}
   */
  protected function getCancelPath() {
    return 'admin/config/user-interface/shortcut/manage/' . $this->menuLink->menu_name;
  }

  /**
   * {@inheritdoc}
   */
  protected function getConfirmText() {
    return t('Delete');
  }

  /**
   * {@inheritdoc}
   */
  public function buildForm(array $form, array &$form_state, MenuLink $menu_link = NULL) {
    $this->menuLink = $menu_link;
    return parent::buildForm($form, $form_state);
  }

  /**
   * {@inheritdoc}
   */
  public function submitForm(array &$form, array &$form_state) {
    menu_link_delete($this->menuLink->mlid);
    $set_name = str_replace('shortcut-', '', $this->menuLink->menu_name);
    $form_state['redirect'] = 'admin/config/user-interface/shortcut/manage/' . $set_name;
    drupal_set_message(t('The shortcut %title has been deleted.', array(
      '%title' => $this->menuLink->link_title,
    )));
  }

}