Add simple regression test for issue #3994 "Subversion working copies that
contain 'svn lock'-style locks cannot be upgraded" and mix it with a few
deleted states to mix this test with shadowed node states.

* subversion/tests/cmdline/upgrade_tests.py
  (upgrade_locked): New function.
  (test_list): Add upgrade_locked.


git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1160682 13f79535-47bb-0310-9956-ffa450edef68