woothemes/woocommerce — pull request #3348 by franticpsyx (2013-06-16 10:42:52+00:00)
Title: Cart values required in woocommerce_checkout_product_title

The values['data'] bit does not contain any cart item data added via hooks by extensions. This is necessary to identify/retrieve special data such as parent-child relationships in the cart, etc.

Changing this second argument might cause issues to extensions that already use this hook, so it would probably be wise to check if anyone is using this at the moment.