Follow-up to r1079508, fixing what is surely a SEGFAULT in the making.
Follow-up to r1079508, fixing what is surely a SEGFAULT in the making.

* subversion/libsvn_client/deprecated.c
  (downgrade_commit_copied_notify_func): Don't try to call a NULL function.

git-svn-id: f8a4e5e023278da1e04e203c7fe051e3c4285d88@1079512 13f79535-47bb-0310-9956-ffa450edef68

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