Resolve 4 uninitialized variable warnings in libsvn_ra_serf. The uninitialized pointers could be dereferenced on receiving an invalid authentication header.
Resolve 4 uninitialized variable warnings in libsvn_ra_serf. The
uninitialized pointers could be dereferenced on receiving an invalid
authentication header.

* subversion/libsvn_ra_serf/auth.c
  (svn_ra_serf__handle_auth): Initialize a few variables to NULL that were
    not set but read anyway, when an invalid authentication header is
    received from a server.


git-svn-id: f8a4e5e023278da1e04e203c7fe051e3c4285d88@876056 13f79535-47bb-0310-9956-ffa450edef68

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