Error: invalid parameter paths

When I am installing drush using

class {'drush::git::drush':
    git_branch => '6.x',
    update     => true,
  }

I got error:
Error: Invalid parameter paths at /etc/puppet/modules/drush/manifests/git.pp:52 on node packer-virtualbox.vagrantup.com

Even though when I do include drush::git::drush drush is installed properly.

It looks like it tries to include class drush::git instead and it requires path parameter.

Please advise how properly to install drush using class notation as I do want to pass branch and update parameters.

Thanks