Fix a data loss when 'svnadmin upgrade' gets interrupted after packing the revprops but before bumping the format file.  In that case, the non-packed revprops would have already been deleted but the next 'svnadmin upgrade' would drop the packed shard as well and then fail to repack.
Fix a data loss when 'svnadmin upgrade' gets interrupted after packing the
revprops but before bumping the format file.  In that case, the non-packed
revprops would have already been deleted but the next 'svnadmin upgrade'
would drop the packed shard as well and then fail to repack.

The fix is to defer the cleanup until after the format bump.

* subversion/libsvn_fs_fs/fs_fs.c
  (upgrade_pack_revprops): don't remove the non-packed shards here ...
  (upgrade_cleanup_pack_revprops): ... but in this new function
  (upgrade_body): call the cleanup after the format bump


git-svn-id: f8a4e5e023278da1e04e203c7fe051e3c4285d88@1494298 13f79535-47bb-0310-9956-ffa450edef68

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