ra_serf: clean the cached realm string on the session after authentication  succeeded, so that we know when the server asks credentials the second time. 
ra_serf: clean the cached realm string on the session after authentication 
succeeded, so that we know when the server asks credentials the second time. 

Found by: Bert Huijben <b.huijben@competence.biz>

* subversion/libsvn_ra_serf/util.c
  (handle_response): reset realm string on session.



git-svn-id: f8a4e5e023278da1e04e203c7fe051e3c4285d88@869974 13f79535-47bb-0310-9956-ffa450edef68

wbond/subversion,YueLinHo/Subversion,wbond/subversion,wbond/subversion,wbond/subversion,wbond/subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,wbond/subversion,YueLinHo/Subversion,wbond/subversion,YueLinHo/Subversion,YueLinHo/Subversion