Changes to ghc

Changes to ghc:
commit fe8a378ceb457fc8cdf97211fddf780f3fb1857f
Author: Joachim Breitner <mail@joachim-breitner.de>
Date:   Sat May 10 18:28:44 2014 +0200

    Revert output of T5979

    this reverts 12332f1. The error message changes when there are two
    versions of transformers in the database, one of them hidden. That might
    be a bug of its own, but for now lets make the test case succeed after a
    fresh build. Affected developers should probably
    $ ./inplace/bin/ghc-pkg unregister transformers-0.3.0.0