getCredentials() responsibilities split

Since [Symfony 4.0](Symfony 4.0) getCredentials() responsibilities has been split into 2 methods:

// BEFORE
use Symfony\Component\Security\Guard\AbstractGuardAuthenticator;

class TokenAuthenticator extends AbstractGuardAuthenticator
{
public function getCredentials(Request request) { if (!token = $request->headers->get(‘X-AUTH-TOKEN’)) {
return null;
}

    return ['token' => $token];
}

}

// AFTER
class TokenAuthenticator extends AbstractGuardAuthenticator
{
public function supports(Request request) { return request->headers->has(‘X-AUTH-TOKEN’);
}

public function getCredentials(Request $request)
{
    return ['token' => $request->headers->get('X-AUTH-TOKEN')];
}

}