Add 8 related regression tests to op-depth tests, of which a few segfault
and/or abort in Subversion 1.8 caused by various unhandled corner cases
in the move-update tree conflict handling.

These tests are loosely based on the scenario in the 'move many and
add-on-update' test in move_tests.py

* subversion/libsvn_wc/wc_db_update_move.c
  (mark_tree_conflict): Replace segfault with assertion on an invalid child
    path.

* subversion/tests/libsvn_wc/op-depth-test.c
  (init_move4): New helper function.
  (del4_update_edit_AAA,
   del4_update_delete_AAA,
   del4_update_add_AAA,
   del4_update_delself_AAA,
   move4_update_edit_AAA,
   move4_update_delete_AAA,
   move4_update_add_AAA,
   move4_update_delself_AAA): New test functions.
  (test_funcs): Add all tests as XFail.


git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1538639 13f79535-47bb-0310-9956-ffa450edef68