menu_ui_menu_predelete

menu_ui_menu_predelete(Menu $menu)

function menu_ui_menu_predelete(Menu $menu) {
  // Delete all links from the menu.
  /** @var \Drupal\Core\Menu\MenuLinkManagerInterface $menu_link_manager */
  $menu_link_manager = \Drupal::service('plugin.manager.menu.link');
  $menu_link_manager->deleteLinksInMenu($menu->id());
}