Originally removed in 86b775d0 as part of the enhancement that allows $(html, props) to use any $.fn method.

Although $.attrFn is undocumented it appears to be a poorly kept secret. jQuery Mobile 1.1 is using it and it's the topic of several blog/StackOverflow posts. Leave an empty object here as a dumpster for now, but it's coming out for good in 1.9.