Comment 5 for bug 1319506

After many tests following your first recommendation, I find out that there is a strange appearance that mysql_stmt_execute fails, and mysql_stmt_errno returns zero! If the statement is not re-prepared in this situation, mysql_stmt_execute will fail at the next time, and mysql_stmt_errno will return 1243. So in the patch file, the condition of statement re-preparing is removed. In other words, no matter what is returned by mysql_stmt_errno, the statement will be re-prepared and then executed in the next loop.