woothemes/woocommerce — pull request #851 by curtismchale (2012-03-19 18:31:44+00:00)
Title: Cleans up debug notices on the tax class if the user has not saved any option on the backend of the site.

There are a bunch of debug notices when the user has not set anything
for their tax class (in the admin). This make all of them clean and
quiet in the header of the site and on the checkout page.