-ddump-splices does not parenthesize visible type applications correctly

So many -ddump-splices bugs...

{-# LANGUAGE TemplateHaskell #-}
{-# LANGUAGE TypeApplications #-}
{-# OPTIONS_GHC -ddump-splices #-}
module Bug where

import Data.Proxy

$([d| f :: Proxy (Int -> Int)
      f = Proxy @(Int -> Int)
    |])

$ /opt/ghc/8.6.1/bin/ghci Bug.hs
GHCi, version 8.6.0.20180627: http://www.haskell.org/ghc/  :? for help
Loaded GHCi configuration from /home/rgscott/.ghci
[1 of 1] Compiling Bug              ( Bug.hs, interpreted )
Bug.hs:(8,3)-(10,6): Splicing declarations
    [d| f_a1Dg :: Proxy (Int -> Int)
        f_a1Dg = Proxy @(Int -> Int) |]
  ======>
    f_a4tx :: Proxy (Int -> Int)
    f_a4tx = Proxy @Int -> Int

Ack—Proxy @Int -> Int should actually be Proxy @(Int -> Int).

Trac metadata

Trac field	Value
Version	8.4.3
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	Compiler
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