Removed wrong fix for the bug#27006.
  The bug was added by the fix for the bug#19978 and fixed by Monty on 2007/02/21.
trigger.test, trigger.result:
  Corrected test case for the bug#27006.


sql/sql_insert.cc:
  Removed wrong fix for the bug#27006.
  The bug was added by the fix for the bug#19978 and fixed by Monty on 2007/02/21.
mysql-test/t/trigger.test:
  Corrected test case for the bug#27006.
mysql-test/r/trigger.result:
  Corrected test case for the bug#27006.