Change from 7.10.3 to current master

[Alan & Kim Zimmerman]

I am in the process of updating ghc-exactprint for current GHC master.

One of the tests has the following in it

-----------------------------
{-# LANGUAGE TypeOperators #-}

type family (r1 :++: r2); infixr 5 :++:
type instance r :++: Nil = r
type instance r1 :++: r2 :> a = (r1 :++: r2) :> a
------------------------------

Current GHC master rejects this with

/tmp/Foo.hs:5:15: error:
    Malformed head of type or class declaration: r1 :++: r2 :> a

Is this expected, or a bug?

Alan