Fix a segfault in the python tests.
Fix a segfault in the python tests.

The problem here is that we're using a pre-1.5 log message callback function
to call a pre-1.5 API.  That's all well and good, except that the callback
doesn't really behave like it's pre-1.5.  Instead, it attempts to convert the
incoming svn_client_commit_item2_t references to svn_client_commit_item3_t
references, which summarily results in a segfault.

There might be a better, more complete solution to this problem, but that will
take more swig-fu than I can muster right now.

Found by: markphip

* subversion/bindings/swig/python/tests/client.py
  (SubversionClientTestCase.setUp): Use a 1.5-era log message callback in the
    client context, instead of a pre-1.5 version.
  (SubversionClientTestCase.testMethodCalls): Update references.

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