mozilla/kuma — pull request #1611 by darkwing (2013-11-07 15:03:24+00:00)
Title: Implement microdata for bredcrumbs for Google Search results.

To test:

Create a 3-level deep document, then paste the crumb contents here:

http://www.google.com/webmasters/tools/richsnippets

You'll see the correct breadcrumb structure below it.