winter/modules/backend/facades/BackendMenu.php

<?php namespace Backend\Facades;

use October\Rain\Support\Facade;

class BackendMenu extends Facade
{
    /**
     * Get the registered name of the component.
     * 
     * Resolves to:
     * - Backend\Classes\NavigationManager
     * 
     * @return string
     */
    protected static function getFacadeAccessor()
    {
        return 'backend.menu';
    }
}