Sync FSX with FSFS.  Block revisions addressing mode changes:
r1637184, r1637186, r1637330, r1637358, r1637393, r1640197, r1640915
and r1641013.

* subversion/libsvn_fs_x:
  Update mergeinfo.


git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1645579 13f79535-47bb-0310-9956-ffa450edef68