Update password collection in checkout to use FAPI's password_confirm

I was poking through the code that validates the new user info in uc_cart_checkout_pane.inc::uc_checkout_pane_customer(), and I noticed you've got if ($arg2['new_account']['pass'] != $arg2['new_account']['pass_confirm']) { //error }. This works great except it does type conversion and will allow a few false matches through. Try 999 and 999.0, they are not the same obviously but will pass validation.

Drupal core had this bug as well until very recently: [[398902]].

Possible solutions: use strcmp() instead of !=, this will validate properly. Or leverage password_confirm_validate() somehow instead?

Actually, now that I'm looking at the form, why isn't it using the password_confirm FAPI element? This gets automatically expanded into a password and confirmation field, and handles validation. Set $contents['new_account']['pass']['#type'] = 'password_confirm' and then you don't need $contents['new_account']['pass_confirm'] at all?