This fixed a bug in prepared statements when used with outher joins
Fixed a bug in SUM(DISTINCT) when used with prepared statements.
Some safety fixes in test scripts to ensure that previous test failures shouldn't affect other tests


mysql-test/r/mysqldump.result:
  Safety fix if a previous test would fail
mysql-test/r/show_check.result:
  Safety fix if a previous test would fail
mysql-test/r/sp.result:
  Fix for --ps-protocol
mysql-test/r/synchronization.result:
  Safety fix if a previous test would fail
mysql-test/r/system_mysql_db.result:
  Safety fix if a previous test would fail
mysql-test/t/mysqldump.test:
  Safety fix if a previous test would fail
mysql-test/t/select.test:
  Safety fix if a previous test would fail
mysql-test/t/show_check.test:
  Safety fix if a previous test would fail
mysql-test/t/sp.test:
  fix for --ps-protocol
mysql-test/t/strict.test:
  Fix for --ps-protocol
mysql-test/t/synchronization.test:
  Safety fix if a previous test would fail
mysql-test/t/system_mysql_db.test:
  Safety fix if a previous test would fail
sql/item_sum.cc:
  Fix bug in SUM(DISTINCT...) when using with prepared statements
sql/item_sum.h:
  Fix bug in SUM(DISTINCT...) when using with prepared statements
sql/mysql_priv.h:
  Better handling of ensuring that setup_tables() are not called twice
sql/sql_base.cc:
  Better handling of ensuring that setup_tables() are not called twice
sql/sql_insert.cc:
  Better handling of ensuring that setup_tables() are not called twice
sql/sql_parse.cc:
  Better handling of ensuring that setup_tables() are not called twice
sql/sql_prepare.cc:
  Better handling of ensuring that setup_tables() are not called twice
sql/sql_select.cc:
  Better handling of ensuring that setup_tables() are not called twice
sql/sql_union.cc:
  Better handling of ensuring that setup_tables() are not called twice
sql/sql_update.cc:
  Better handling of ensuring that setup_tables() are not called twice
sql/table.h:
  Better handling of ensuring that setup_tables() are not called twice