Speed up the metadata check for log. addressed FSFS repos.
Speed up the metadata check for log. addressed FSFS repos.

* subversion/libsvn_fs_fs/cached_data.c
  (svn_fs_fs__check_rep): Reuse the rev / pack file through the same
                          hinting mechanism as in older formats.

git-svn-id: f8a4e5e023278da1e04e203c7fe051e3c4285d88@1640062 13f79535-47bb-0310-9956-ffa450edef68

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