DEFAULT (with no argument) or to the field's type's default by not being
listed in the list of fields being inserted. (Bug #5986)                    


sql/item.cc:
  Add Item_default_value::save_in_field(), with check for setting fields
  with no default value set.
sql/item.h:
  Implementation of Item_default_value::save_in_field moved to item.cc
sql/sql_insert.cc:
  Call check_that_all_fields_are_given_values() if no values were
  given and we would be filling row with all default values
mysql-test/t/strict.test:
  Add tests for setting fields to DEFAULT in traditional and regular modes
mysql-test/r/strict.result:
  Add results