Simplify merge code a tiny bit.
Simplify merge code a tiny bit.

* subversion/libsvn_client/merge.c
  (calculate_remaining_ranges, find_gaps_in_merge_source_history,
   do_file_merge): Replace a call to svn_ra__get_fspath_relative_to_root()
    with a simpler call to svn_client__pathrev_fspath().
  (do_mergeinfo_aware_dir_merge): Rename 'primary_loc' to 'primary_src' for
  consistency.


git-svn-id: f8a4e5e023278da1e04e203c7fe051e3c4285d88@1339871 13f79535-47bb-0310-9956-ffa450edef68

YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion