after merge fix

mysql-test/r/subselect.result:
  changes in plans because we do not check nulls where nuul is impossible
  changed warning number

mysql-test/r/subselect.result

@@ -1160,9 +1160,9 @@ SELECT 0 IN (SELECT 1 FROM t1 a);
 EXPLAIN EXTENDED SELECT 0 IN (SELECT 1 FROM t1 a);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	NULL	NULL	NULL	NULL	NULL	NULL	NULL	No tables used
-2	DEPENDENT SUBQUERY	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Impossible WHERE noticed after reading const tables
+2	DEPENDENT SUBQUERY	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Impossible WHERE
 Warnings:
-Note	1003	select high_priority <in_optimizer>(0,<exists>(select 1 AS `Not_used` from test.t1 a where isnull(1) having <is_not_null_test>(1) limit 1)) AS `0 IN (SELECT 1 FROM t1 a)`
+Note	1003	select high_priority <in_optimizer>(0,<exists>(select 1 AS `Not_used` from test.t1 a limit 1)) AS `0 IN (SELECT 1 FROM t1 a)`
 INSERT INTO t1 (pseudo) VALUES ('test1');
 SELECT 0 IN (SELECT 1 FROM t1 a);
 0 IN (SELECT 1 FROM t1 a)
@@ -1170,9 +1170,9 @@ SELECT 0 IN (SELECT 1 FROM t1 a);
 EXPLAIN EXTENDED SELECT 0 IN (SELECT 1 FROM t1 a);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	NULL	NULL	NULL	NULL	NULL	NULL	NULL	No tables used
-2	DEPENDENT SUBQUERY	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Impossible WHERE noticed after reading const tables
+2	DEPENDENT SUBQUERY	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Impossible WHERE
 Warnings:
-Note	1003	select high_priority <in_optimizer>(0,<exists>(select 1 AS `Not_used` from test.t1 a where isnull(1) having <is_not_null_test>(1) limit 1)) AS `0 IN (SELECT 1 FROM t1 a)`
+Note	1003	select high_priority <in_optimizer>(0,<exists>(select 1 AS `Not_used` from test.t1 a limit 1)) AS `0 IN (SELECT 1 FROM t1 a)`
 drop table t1;
 CREATE TABLE `t1` (
 `i` int(11) NOT NULL default '0',
@@ -1657,7 +1657,7 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	tt	ALL	NULL	NULL	NULL	NULL	12	Using where
 2	DEPENDENT SUBQUERY	t1	eq_ref	PRIMARY	PRIMARY	4	test.tt.id	7	Using where; Using index
 Warnings:
-Note	1275	Field or reference 'tt.id' of SELECT #2 was resolved in SELECT #1
+Note	1276	Field or reference 'tt.id' of SELECT #2 was resolved in SELECT #1
 Note	1003	select high_priority test.tt.id AS `id`,test.tt.text AS `text` from test.t1 tt where not(exists(select test.t1.id AS `id` from test.t1 where ((test.t1.id < 8) and ((test.t1.id = test.tt.id) or isnull(test.t1.id))) having (test.t1.id is not null) limit 1))
 insert into t1 (id, text) values (1000, 'text1000'), (1001, 'text1001');
 create table t2 (id int not null, text varchar(20) not null default '', primary key (id));