ctype_utf8.test, ctype_utf8.result:
  Adding test case.
item.h:
item.cc:
  Adding Item_param::safe_charset_converter


sql/item.cc:
   Bug#12371: executing prepared statement fails (illegal mix of collations)
  Adding Item_param::safe_charset_converter
sql/item.h:
  Adding Item_param::safe_charset_converter
mysql-test/r/ctype_utf8.result:
  Adding test case.
mysql-test/t/ctype_utf8.test:
  Adding test case.