You have requested a non-existent service "knp_menu.menu_provider.chain"

```
  [Symfony\Component\DependencyInjection\Exception\ServiceNotFoundException]
  You have requested a non-existent service "knp_menu.menu_provider.chain". Did you mean this:  "knp_menu.menu_provider"?
```

in my composer.json, got : "symfony/symfony": "2.8.*@dev"

got this error after a composer update
