Follow-up for r19509 with a test for issue #2275.
Follow-up for r19509 with a test for issue #2275.

Verify that both ra_svn and ra_dav both return the same error message
when (un)locking an already (un)locked file.

* subversion/tests/cmdline/lock_tests.py
  (steal_lock): remove '423 Locked' error message
  (unlock_already_unlocked_files): ditto

jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion