Fix security definer functions with polymorphic arguments. This case has

never worked because fmgr_security_definer() neglected to pass the fn_expr
information through.  Per report from Viatcheslav Kalinin.

src/backend/utils/fmgr/fmgr.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/fmgr/fmgr.c,v 1.107 2007/07/13 02:25:48 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/fmgr/fmgr.c,v 1.108 2007/07/31 15:49:49 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -859,6 +859,7 @@ fmgr_security_definer(PG_FUNCTION_ARGS)
 
 		fmgr_info_cxt_security(fcinfo->flinfo->fn_oid, &fcache->flinfo,
 							   fcinfo->flinfo->fn_mcxt, true);
+		fcache->flinfo.fn_expr = fcinfo->flinfo->fn_expr;
 
 		tuple = SearchSysCache(PROCOID,
 							   ObjectIdGetDatum(fcinfo->flinfo->fn_oid),