Description:
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RecursiveIteratorIterator constructor fails to recognize mode constants.

The constructor works fine when passed only a RecursiveIterator object.  It also functions correctly if passed a RecursiveIterator object and an integer (0,1,2, etc) as the second (mode) argument.  However, if one attempts to pass a documented constant keyword (RIT_SELF_FIRST or SELF_FIRST), the constructor fails.

Note: different documentations show different constant definitions (RIT_SELF_FIRST vs SELF_FIRST). I have tried both, and neither one works.

Reproduce code:
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class Rit implements RecursiveIterator {...}

$test = new Rit();

//work fine
$rii = new RecursiveIteratorIterator($test);
$rii = new RecursiveIteratorIterator($test, 1);

//do not work
$rii = new RecursiveIteratorIterator($test, RIT_SELF_FIRST);
$rii = new RecursiveIteratorIterator($test, SELF_FIRST);

//even tried this, with no avail
$rii = new RecursiveIteratorIterator($test, RecursiveIteratorIterator::RIT_SELF_FIRST);
$rii = new RecursiveIteratorIterator($test, RecursiveIteratorIterator::SELF_FIRST);


Expected result:
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A RecursiveIteratorIterator object

Actual result:
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Notice: Use of undefined constant RIT_SELF_FIRST - assumed 'RIT_SELF_FIRST' in /www/rit.class.php on line 276

(or Notice: Use of undefined constant SELF_FIRST - assumed 'SELF_FIRST' in /www/rit.class.php on line 276)


Fatal error: Uncaught exception 'InvalidArgumentException' with message 'An instance of RecursiveIterator or IteratorAggregate creating it is required' in /www/rit.class.php:276 Stack trace: #0 /www/rit.class.php(276): RecursiveIteratorIterator->__construct(Object(treeIterator), 'RIT_SELF_FIRST') ...