Partial fix for issue #4174.
Partial fix for issue #4174.

* subversion/libsvn_ra_serf/util.c:
  (handle_response): Connection abort is now an error where serf can recover
   from, so treat it as non-fatal error.

git-svn-id: f8a4e5e023278da1e04e203c7fe051e3c4285d88@1388975 13f79535-47bb-0310-9956-ffa450edef68

YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion