* subversion/libsvn_fs_x/cached_data.c
  (svn_fs_x__rep_chain_length): The sub-pool is actually an iteration pool
                                used in a non-standard way.  Rename and
                                document the usage.

Suggested by: rhuijben


git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1627946 13f79535-47bb-0310-9956-ffa450edef68