Following up on r1551524, fix committing a move from an external to an
ancestor directory or moving the other way around.

* subversion/libsvn_client/copy.c
  (do_wc_to_wc_moves): Don't assume that child directories are always part
    of the parent working copy for locking.

* subversion/tests/cmdline/move_tests.py
  (move_to_from_external): Remove XFail marker and fix commit command.


git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1551579 13f79535-47bb-0310-9956-ffa450edef68