mozilla/rust — pull request #14011 by TheHydroImpulse (2014-05-07 07:34:24+00:00)
Title: Move the mutex module out of std::unstable and straight into libstd.

This is not a breaking change as mutex is re-exported in std::unstable
to make a transition easier. `std::mutex` is also marked as unstable.

This change is related to #1457 and comment
https://github.com/mozilla/rust/issues/1457#issuecomment-40523194