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  	Desugar bindings into Rec groups more often
		[Part 2]
  	-------------------------------------------

	** MERGE PLEASE **

	  [I forgot the unlifted case.]

  In rather obscure cases (involving functional dependencies)
  it is possible to get an AbsBinds [] [] (no tyvars, no dicts)
  which nevertheless has some "dictionary bindings".  These
  come out of the typechecker in non-dependency order, so we
  need to Rec them just in case.

  It turns out to be a bit awkward.  The smallest fix is
  to make dsLet always make a Rec; brutal but correct.