[GHC] #11355: TypeApplications + RankNTypes permits "impredicativity"

[GHC]

#11355: TypeApplications + RankNTypes permits "impredicativity"
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        Reporter:  adamgundry        |                Owner:  goldfire
            Type:  bug               |               Status:  merge
        Priority:  normal            |            Milestone:  8.0.1
       Component:  Compiler          |              Version:  7.11
      Resolution:                    |             Keywords:
                                     |  TypeApplications
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
                                     |  typecheck/should_fail/T11355
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by bgamari):

 Cherry-picked to `ghc-8.0` as d4661c1adc732b12d39a6aab4a3f5a8c61e27dde.

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11355#comment:6>
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