Remove special case in parser
Remove special case in parser

There was a special case that triggered a parse error in this course

          def lift[T <: Type](tp: T): (RecType => T) = arg match {
            case rt0: RecType => tp.subst(rt0, _).asInstanceOf[T]
            case _ => (x => tp)
          }

The problem was that the rhs of the first case became a Function node, which
caused a premature return from the case clause sequence. I could not determine
anymore what the purpose of the removed case in the parser was; all tests compile
without it.

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