Description:
------------
RecursiveArrayIterator doesn't have constants from parent class

See https://3v4l.org/7fVc4

Test script:
---------------
<?php

class Foo extends \ArrayIterator
{
    
}

$fooReflection = new \ReflectionClass(\Foo::class);
$recursiveArrayIteratorReflection = new \ReflectionClass(\RecursiveArrayIterator::class);

printf("%d constants in %s, ", count($fooReflection->getConstants()), \Foo::class);
if ($fooReflection->getParentClass()) {
    printf("%s extends %s\n", Foo::class, $fooReflection->getParentClass()->getName());
}
printf("%d constants in %s, ", count($recursiveArrayIteratorReflection->getConstants()), \RecursiveArrayIterator::class);
if ($recursiveArrayIteratorReflection->getParentClass()) {
    printf("%s extends %s\n", \RecursiveArrayIterator::class, $recursiveArrayIteratorReflection->getParentClass()->getName());
}
printf("%d constants in %s\n", count((new \ReflectionClass(\ArrayIterator::class))->getConstants()), \ArrayIterator::class);

Expected result:
----------------
2 constants in Foo, Foo extends ArrayIterator
3 constants in RecursiveArrayIterator, RecursiveArrayIterator extends ArrayIterator
2 constants in ArrayIterator

Actual result:
--------------
2 constants in Foo, Foo extends ArrayIterator
1 constants in RecursiveArrayIterator, RecursiveArrayIterator extends ArrayIterator
2 constants in ArrayIterator