User selectable roles not working again

Hello,

I've noticed that user selectable roles are broken again. The reason for that is because array_unshift doens't work like expected with numerical keys. See

array_unshift() prepends passed elements to the front of the array. Note that the list of elements is prepended as a whole, so that the prepended elements stay in the same order. All numerical array keys will be modified to start counting from zero while literal keys won't be touched.

from here: http://php.net/manual/en/function.array-unshift.php

So for the case when "none" is added to the array, the rids are lost. The fix would be to replace array_unshift with something like this:

$roles = array(0 => t('None')) + $roles;