Relieve some memory pressure by delaying XML parser creation until we start to receive a response.  Otherwise, we'd create the parser as soon as we queue the request meaning we could have up to 1,000 parsers created at a time sitting around waiting for serf to give us data.
Relieve some memory pressure by delaying XML parser creation until we start
to receive a response.  Otherwise, we'd create the parser as soon as we
queue the request meaning we could have up to 1,000 parsers created at a
time sitting around waiting for serf to give us data.

* subversion/libsvn_ra_serf/util.c
  (expat_response_handler): Create parser when needed on first one.
  (svn_ra_serf__create_expat_handler): Delay parser and actually use
  cleanup_pool.

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