On the log-addressing branch:  Since we verify index vs. index and
index vs. pack / rev file, we can now simplify the rep-cache.db
verification by simply comparing it with the indexes.  Physical
addressing mode continues to use the conventional approach.

* subversion/libsvn_fs_fs/cached_data.c
  (svn_fs_fs__check_rep): verify that all rep-cache.db entries
                          refer to actual representation items

git-svn-id: https://svn.apache.org/repos/asf/subversion/branches/log-addressing@1516340 13f79535-47bb-0310-9956-ffa450edef68