Propage the handler into the response processing callbacks.
Propage the handler into the response processing callbacks.

* subversion/libsvn_ra_serf/update.c:
  (report_fetch_t): add HANDLER field
  (handle_fetch, handle_stream, handle_local_fetch): assert we have
    the handler, and use it.
  (fetch_file, svn_ra_serf__get_file): initialize HANDLER


git-svn-id: f8a4e5e023278da1e04e203c7fe051e3c4285d88@1335365 13f79535-47bb-0310-9956-ffa450edef68

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