Description:
------------
mysqi_error() and mysqli_errno() does not capture last error message 
and error code if mysqli_real_query() executes on a stored procedure 
that returns multiple result sets but one of them is an error. 

As you can see from the below code, I have a SP that basically a set 
of SELECTs but the last one is invalid by intention. If executing the 
SP (e.x: CALL p2(2, 5) ) in a MySQL Query Manager, the following 
warning will show up:

(1 row(s) returned)
Execution Time : 00:00:00:000
Transfer Time  : 00:00:00:000
Total Time     : 00:00:00:000

(1 row(s) returned)
Execution Time : 00:00:00:000
Transfer Time  : 00:00:00:000
Total Time     : 00:00:00:000

(1 row(s) returned)
Execution Time : 00:00:00:000
Transfer Time  : 00:00:00:000
Total Time     : 00:00:00:000

Query : CALL p2(2, 5) 
Error Code : 1146
Table 'test.non_existent_' doesn't exist
Execution Time : 00:00:00:000
Transfer Time  : 00:00:00:000
Total Time     : 00:00:00:000

However, mysqli does not work that way. It does not know what happens 
with the last query. It simply knows the last query does not return a 
result set.



Reproduce code:
---------------
<?php

/*

DELIMITER $$

CREATE PROCEDURE p2(X INT, Y INT)
    	DETERMINISTIC
    	BEGIN
        	SELECT
            	X ;
        	SELECT
            	X AS first_param,
            	Y AS second_param;
        	SELECT
            	X,
            	Y,
           		X + Y AS sum_xy,
            	X * Y AS prod_xy;
        	SELECT 1 FROM non_existent_; -- Intentional error
    	END$$

DELIMITER ;
*/


$conn = mysqli_connect("localhost", "root", "123456", "test");

/* check connection */
if (mysqli_connect_errno()) {
    printf("Connect failed: %s\n", mysqli_connect_error());
    exit();
}

$query   = "CALL p2(2, 5)";
$success = mysqli_real_query($conn, $query);

if (false === $success)
{
    var_dump(mysqli_error($conn));
}

$i = 0;
do
{
    $result = mysqli_store_result($conn);
    if (false !== $result)
    {
        echo ++$i."\n";
    }
    else
    {
        var_dump(mysqli_error($conn));
    }

} while (mysqli_more_results($conn) && mysqli_next_result($conn));

/* close connection */
mysqli_close($conn);

?>

Expected result:
----------------
1
2
3
string(0) "Table 'test.non_existent_' doesn't exist"

Actual result:
--------------
1
2
3