Merge with 4.1 to get new thd->mem_root handling

BitKeeper/etc/ignore:
  auto-union
client/mysqldump.c:
  Auto merged
client/mysqltest.c:
  Auto merged
innobase/include/row0mysql.h:
  Auto merged
libmysql/libmysql.c:
  Auto merged
mysql-test/r/ctype_ucs.result:
  Auto merged
mysql-test/r/fulltext.result:
  Auto merged
mysql-test/r/func_in.result:
  Auto merged
mysql-test/r/ps.result:
  Auto merged
mysql-test/r/ps_2myisam.result:
  Auto merged
mysql-test/r/ps_3innodb.result:
  Auto merged
mysql-test/r/ps_4heap.result:
  Auto merged
mysql-test/r/ps_5merge.result:
  Auto merged
mysql-test/r/ps_6bdb.result:
  Auto merged
mysql-test/r/type_float.result:
  Auto merged
mysql-test/r/user_var.result:
  Auto merged
mysql-test/t/innodb.test:
  Auto merged
mysql-test/t/user_var.test:
  Auto merged
mysql-test/t/variables.test:
  Auto merged
sql/ha_berkeley.cc:
  Auto merged
sql/ha_innodb.cc:
  Auto merged
sql/ha_innodb.h:
  Auto merged
sql/ha_ndbcluster.h:
  Auto merged
sql/item.cc:
  Auto merged
sql/item_cmpfunc.cc:
  Auto merged
sql/item_func.cc:
  Auto merged
sql/item_sum.cc:
  Auto merged
sql/item_timefunc.cc:
  Auto merged
sql/log_event.cc:
  Auto merged
sql/mysql_priv.h:
  Auto merged
sql/mysqld.cc:
  Auto merged
sql/repl_failsafe.cc:
  Auto merged
sql/set_var.cc:
  Auto merged
sql/sql_acl.cc:
  Auto merged
sql/sql_db.cc:
  Auto merged
sql/sql_error.cc:
  Auto merged
sql/sql_help.cc:
  Auto merged
sql/sql_insert.cc:
  Auto merged
sql/sql_prepare.cc:
  Auto merged
sql/sql_select.h:
  Auto merged
sql/sql_yacc.yy:
  Auto merged

mysql-test/r/func_in.result

@@ -179,3 +179,9 @@ select 1 in ('1.1',2);
 select 1 in ('1.1',2.0);
 1 in ('1.1',2.0)
 0
+create table t1 (a char(20) character set binary);
+insert into t1 values ('aa'), ('bb');
+select * from t1 where a in (NULL, 'aa');
+a
+aa
+drop table t1;