jquery/sizzle — pull request #100 by gibson042 (2012-04-05 15:08:40+00:00)
Title: jQuery ticket 11539: Sizzle.contains(container, textNode)

Also safe when `b` is a document fragment or descendant thereof, but (as is currently the case) inaccurate when `a` is also a document or fragment.

Comes with bonus unit tests!