Make pg_dumpall's database ACL query independent of hash table order.

Previously GRANT order on databases was not well defined, due to the use
of EXCEPT without an ORDER BY.  Add an ORDER BY, adapt test output.

I don't, at the moment, see reason to backpatch this.

Author: anarazel

src/bin/pg_dump/pg_dumpall.c

@@ -1307,11 +1307,13 @@ dumpCreateDB(PGconn *conn)
 						   "pg_encoding_to_char(d.encoding), "
 						   "datcollate, datctype, datfrozenxid, datminmxid, "
 						   "datistemplate, "
-						   "(SELECT pg_catalog.array_agg(acl) FROM (SELECT pg_catalog.unnest(coalesce(datacl,pg_catalog.acldefault('d',datdba))) AS acl "
-						   "EXCEPT SELECT pg_catalog.unnest(pg_catalog.acldefault('d',datdba))) as foo)"
+						   "(SELECT pg_catalog.array_agg(acl ORDER BY acl::text) FROM ( "
+						   "  SELECT pg_catalog.unnest(coalesce(datacl,pg_catalog.acldefault('d',datdba))) AS acl "
+						   "  EXCEPT SELECT pg_catalog.unnest(pg_catalog.acldefault('d',datdba))) as datacls)"
 						   "AS datacl, "
-						   "(SELECT pg_catalog.array_agg(acl) FROM (SELECT pg_catalog.unnest(pg_catalog.acldefault('d',datdba)) AS acl "
-						   "EXCEPT SELECT pg_catalog.unnest(coalesce(datacl,pg_catalog.acldefault('d',datdba)))) as foo)"
+						   "(SELECT pg_catalog.array_agg(acl ORDER BY acl::text) FROM ( "
+						   "  SELECT pg_catalog.unnest(pg_catalog.acldefault('d',datdba)) AS acl "
+						   "  EXCEPT SELECT pg_catalog.unnest(coalesce(datacl,pg_catalog.acldefault('d',datdba)))) as rdatacls)"
 						   "AS rdatacl, "
 						   "datconnlimit, "
 						   "(SELECT spcname FROM pg_tablespace t WHERE t.oid = d.dattablespace) AS dattablespace "

src/bin/pg_dump/t/002_pg_dump.pl

@@ -2484,6 +2484,7 @@
 		create_sql   => 'REVOKE CONNECT ON DATABASE dump_test FROM public;',
 		regexp       => qr/^
 			\QREVOKE CONNECT,TEMPORARY ON DATABASE dump_test FROM PUBLIC;\E\n
+			\QGRANT CREATE ON DATABASE dump_test TO regress_dump_test_role;\E\n
 			\QGRANT TEMPORARY ON DATABASE dump_test TO PUBLIC;\E
 			/xm,
 		like   => { pg_dumpall_dbprivs => 1, },