patch applied (ghc-6.8/ghc): MERGE to 6.8: Refactor error recovery slightly

[Simon Peyton Jones]

Wed Nov 21 06:32:27 PST 2007  simonpj at microsoft.com
  * MERGE to 6.8: Refactor error recovery slightly
  
  Slightly rejigged from HEAD:
  
    Mostly this patch is refacoring, but it also avoids post-tc zonking if
    the typechecker found errors.  This is good because otherwise with
    DEBUG you can get the "Inventing strangely-kinded TyCon" warning.
  

    M ./compiler/typecheck/TcRnDriver.lhs -11 +12
    M ./compiler/typecheck/TcTyClsDecls.lhs -1 +5