mysql_fetch_field if $field_offset == 0

[paolobia]

check this changes

if $field_offset== 0
mysqli_field_seek is not call and
mysqli_fetch_field fail

function mysql_fetch_field(mysqli_result $result, $field_offset = -1)
{
		if ($field_offset>=0) {
			mysqli_field_seek($result, $field_offset);
		}

        $foo = mysqli_fetch_field($result);

        // increase mysql_fetch_field compatibility ;-)
        if ($foo->flags & 2) $foo->primary_key = 1;
        if ($foo->flags & 4) $foo->unique_key = 1;

	return $foo;
}