mysql-test/r/subselect.result:
  subselect test changed
mysql-test/t/subselect.test:
  INSERT DELAYED INTO t1 (x) VALUES ((SELECT SUM(x) FROM t2));
sql/item.cc:
  avoid resolving of INSER/REPLACE tables field in subqueries
sql/sql_lex.cc:
  Primary (top) simple INSERT/REPLACE st_select_lex indicator
sql/sql_lex.h:
  Primary (top) simple INSERT/REPLACE st_select_lex indicator
sql/sql_yacc.yy:
  Primary (top) simple INSERT/REPLACE st_select_lex indicator