Description:
------------
uasort's  problem  in different version(5.x, 7.x)

Test script:
---------------
<?php
$arr = array(
    38 => ['id' => 38, 'score' => 3.45],
    34 => ['id' => 34, 'score' => 3.45],
    30 => ['id' => 30, 'score' => 3.45],

);
uasort($arr, function ($row_a, $row_b) {                                                                                                                     
    if ($row_a['score'] == $row_b['score']) {
        return 0;
    }
    return ($row_a['score'] >= $row_b['score']) ? -1 : 1;
});

print_r($arr);
                                                                                                                                                 
 ~/test/uasort.php[1]                                                                                                              
[gaozhenan@sjs_85_168 test]$php55 uasort.php 
Array
(
    [30] => Array
        (
            [id] => 30
            [score] => 3.45
        )

    [34] => Array
        (
            [id] => 34
            [score] => 3.45
        )

    [38] => Array
        (
            [id] => 38
            [score] => 3.45
        )

)
[gaozhenan@sjs_85_168 test]$php71 uasort.php   
Array
(
    [38] => Array
        (
            [id] => 38
            [score] => 3.45
        )

    [34] => Array
        (
            [id] => 34
            [score] => 3.45
        )

    [30] => Array
        (
            [id] => 30
            [score] => 3.45
        )

)

Expected result:
----------------
the result in php 7.x should be equal in 5.x

Actual result:
--------------
just opposite