rust-lang/rust — pull request #19642 by aaronweiss74 (2014-12-08 21:28:39+00:00)
Title: Implemented BorrowFrom<Rc<T>> for T.

This was discussed in [#rust-internals](
https://botbot.me/mozilla/rust-internals/2014-12-08/?msg=27077624&page=5). It's a small change.