patch applied (testsuite): Add test for #2678

[Simon Marlow]

Tue Jun 16 03:18:01 PDT 2009  Simon Marlow <marlowsd at gmail.com>
  * Add test for #2678
  Ignore-this: 56189c65917b7da70eb2de8cf294992c
  it's a generic test, so I named it after the operation rather than the
  ticket

    M ./tests/ghc-regress/lib/IO/all.T +2
    A ./tests/ghc-regress/lib/IO/hSetBuffering004.hs
    A ./tests/ghc-regress/lib/IO/hSetBuffering004.stdout

View patch online:
http://darcs.haskell.org/testsuite/_darcs/patches/20090616101801-12142-3ac1a72ca6e495ec9da819febf95936ac0eec068.gz