On the fsfs-format7 branch: Fix pack logic.

* subversion/libsvn_fs_fs/pack.c
  (copy_indexes): move offset to next expected location and compare
   that to actuals to detect duplicates


git-svn-id: https://svn.apache.org/repos/asf/subversion/branches/fsfs-format7@1434961 13f79535-47bb-0310-9956-ffa450edef68