[GHC] #12970: Add default implementation for Bits.bitSize

[GHC]

#12970: Add default implementation for Bits.bitSize
-------------------------------------+-------------------------------------
        Reporter:  txnull            |                Owner:  dfeuer
            Type:  feature request   |               Status:  patch
        Priority:  high              |            Milestone:  ⊥
       Component:  libraries/base    |              Version:
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  Phab:D3723
       Wiki Page:                    |
-------------------------------------+-------------------------------------

Comment (by ekmett):

 I have no objection to filling in a default definition until it gets
 removed. That would make it possible for folks to eventually remove the
 definitions from their code and stay 3-release friendly.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12970#comment:19>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler