Add op-depth test for issue #4436.

* subversion/tests/libsvn_wc/op-depth-test.c
  (move_child_to_parent_revert): New function.
  (test_funcs): Add move_child_to_parent_revert as XFail.

* subversion/libsvn_wc/wc_db_update_move.c
  (svn_wc__db_resolve_break_moved_away_internal): Add assertion to avoid hard
    to diagnose segfault from op-depth-tests.c on the next statement.


git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1530872 13f79535-47bb-0310-9956-ffa450edef68