Not found exception for Twig Function Method class

Steps:
1. Clone the Platform EE demo repo into an empty directory.
2. On current master run `composer update`.
Actual: Exception occurs during post install scripts execution (attached).
Expected: Installation finishes w/o exceptions.

Remarks: Attached is log excerpt also:
request.CRITICAL: Uncaught PHP Exception Symfony\Component\Debug\Exception\ClassNotFoundException: "Attempted to load class "Twig_Function_Method" from the global namespace. Did you forget a "use" statement?" at /var/www/vendor/knplabs/knp-menu/src/Knp/Menu/Twig/MenuExtension.php line 24
"exception":"[object] (Symfony\\Component\\Debug\\Exception
ClassNotFoundException(code: 0): Attempted to load class \"Twig_Function_Method\" from the global namespace.\nDid you forget a \"use\" statement? at /var/www/vendor/knplabs/knp-menu/src/Knp/Menu/Twig/MenuExtension.php:24)