[GHC] #14524: Use sortOn instead of sortWith

[GHC]

#14524: Use sortOn instead of sortWith
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        Reporter:  AndreasK          |                Owner:  AndreasK
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.2.1
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  Other             |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  Phab:D4233
       Wiki Page:                    |
-------------------------------------+-------------------------------------
Changes (by AndreasK):

 * owner:  (none) => AndreasK
 * differential:   => Phab:D4233


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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14524#comment:2>
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