[GHC] #15335: Export `findImportUsage` from `rename/RnNames.hs` module

[GHC]

#15335: Export `findImportUsage` from `rename/RnNames.hs` module
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        Reporter:  chshersh          |                Owner:  (none)
            Type:  feature request   |               Status:  patch
        Priority:  normal            |            Milestone:  8.6.1
       Component:  Compiler          |              Version:  8.4.3
      Resolution:                    |             Keywords:
                                     |  imports,refactoring,export
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  Phab:D4927
       Wiki Page:                    |
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Comment (by Ben Gamari <ben@…>):

 In [changeset:"2b1adaa7817c453df868d928312a9a99a0481eb1/ghc" 2b1adaa/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="2b1adaa7817c453df868d928312a9a99a0481eb1"
 Export findImportUsage and ImportDeclUsage

 Reviewers: bgamari, alpmestan

 Reviewed By: alpmestan

 Subscribers: alpmestan, rwbarton, thomie, carter

 GHC Trac Issues: #15335

 Differential Revision: https://phabricator.haskell.org/D4927
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15335#comment:2>
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