mysql-test/r/case.result:
  Post-review fix for bug #20924
mysql-test/r/func_if.result:
  Post-review fix for bug #20924
mysql-test/r/func_test.result:
  Post-review fix for bug #20924
mysql-test/r/user_var.result:
  Post-review fix for bug #20924
mysql-test/t/case.test:
  Post-review fix for bug #20924
mysql-test/t/func_if.test:
  Post-review fix for bug #20924
mysql-test/t/func_test.test:
  Post-review fix for bug #20924
mysql-test/t/user_var.test:
  Post-review fix for bug #20924
sql/item_func.cc:
  Post-review fix for bug #20924
sql/item_func.h:
  Post-review fix for bug #20924
sql/log_event.cc:
  Post-review fix for bug #20924