orders that cannot be handled by the executioner.


mysql-test/r/bigint.result:
  Added mssing "drop table if exists"
mysql-test/r/join_nested.result:
  Testcase for BUG#13126
mysql-test/t/bigint.test:
  Added mssing "drop table if exists"
mysql-test/t/join_nested.test:
  Testcase for BUG#13126
sql/mysql_priv.h:
  BUG#13126: Added nested_join_map type.
sql/sql_prepare.cc:
  BUG#13126: Don't set NESTED_JOIN::counter to 0 here as it is reset in other place now.
sql/sql_select.cc:
  BUG#13126: When choosing join order for join with nested joins, don't produce join orders
  that the executioner cannot handle. The work is done by check_interleaving_with_nj() and 
  restore_prev_nj_state() functions that are used from the join optimizer to avoid building
  invalid join orders.
sql/sql_select.h:
  BUG#13126: Added JOIN_TAB::embedding_map and JOIN::cur_embedding_map.
sql/table.h:
  BUG#13126: In NESTED_JOIN: added nj_map, added comment about where counter is used.