create user identified WITH mysql_native_password not work

[jackysp]

Please answer these questions before submitting your issue. Thanks!

1. What did you do?
   If possible, provide a recipe for reproducing the error.

    public void testBug19354014() throws Exception {
        if (versionMeetsMinimum(5, 5, 7)) {
            Connection con = null;
            createUser("'bug19354014user'@'%'", "identified WITH mysql_native_password");
            this.stmt.executeUpdate("grant all on *.* to 'bug19354014user'@'%'");
            this.stmt.executeUpdate(versionMeetsMinimum(5, 7, 6) ? "ALTER USER 'bug19354014user'@'%' IDENTIFIED BY 'pwd'"
                    : "set password for 'bug19354014user'@'%' = PASSWORD('pwd')");
            this.stmt.executeUpdate("flush privileges");

            try {
                Properties props = new Properties();
                props.setProperty("useCompression", "true");

                con = getConnectionWithProps(props);
                ((MySQLConnection) con).changeUser("bug19354014user", "pwd");
            } finally {
                this.stmt.executeUpdate("flush privileges");

                if (con != null) {
                    con.close();
                }
            }
        }
    }

2. What did you expect to see?
   It should be OK.

3. What did you see instead?
   createUser("'bug19354014user'@'%'", "identified WITH mysql_native_password"); return an syntax error. "java.sql.SQLException: line 1 column 50 near " mysql_native_password" (total length 72)"

4. What version of TiDB are you using (tidb-server -V or run select tidb_version(); on TiDB)?
   ae2e3ac