Description:
------------
when subclassing SplFileObject and opening it via SplFileInfo->openFile() initialized array properties of the subclass of SplFileInfo are changing to null, while strings are fine.

Test script:
---------------
<?php
class Foo extends SplFileObject
{
        public $bar = 'baz';
        public $bam = array();
	function __construct($file)
	{
		// do stuff
		parent::__construct($file);	
	}
}
$fileInfo = new SplFileInfo('php://temp');
$fileInfo->setFileClass('Foo');
$file = $fileInfo->openFile('r');

print var_dump($file->bar); // is baz
print var_dump($file->bam); // is null or UNKNOWN:0
?>

Expected result:
----------------
I expected var_dump($file->bam) to print an empty array

Actual result:
--------------
null or UNKNOWN:0