[GHC] #10735: Smooth out the differences between `compiler/utils/Pretty.hs` and `libraries/pretty`

[GHC]

#10735: Smooth out the differences between `compiler/utils/Pretty.hs` and
`libraries/pretty`
-------------------------------------+-------------------------------------
        Reporter:  thomie            |                Owner:  thomie
            Type:  task              |               Status:  closed
        Priority:  normal            |            Milestone:  8.0.1
       Component:  Compiler          |              Version:  7.0.1
      Resolution:  fixed             |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #1062, #1176,     |  Differential Rev(s):  Phab:D1130,
  #7666, #8809                       |  Phab:D1132
       Wiki Page:                    |
-------------------------------------+-------------------------------------
Changes (by thomie):

 * status:  patch => closed
 * resolution:   => fixed
 * milestone:  8.2.1 => 8.0.1


Comment:

 This is pretty much done.

 For parity with pretty-1.1.2.1 the following two commits would also be
 needed. I did not land them, because they seem to cause more allocation in
 the compiler (see discussion in
 ​https://github.com/haskell/pretty/pull/9):

 * "Resolve foldr-strictness stack overflow bug"
 * "Special-case reduce for horiz/vert"

 The commits are here: ​https://github.com/thomie/ghc/commits/pretty

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10735#comment:23>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler