Description:
------------
Be aware if You extends SplFixedArray and use toArray method.
                                                                                                                                                    

Test script:
---------------
class MyFixedArray extends \SplFixedArray {                                                                                                                                 
    protected $foo;                                                                                                                                                         
    protected $bar;                                                                                                                                                         
}                                                                                                                                                                           
                                                                                                                                                                            
$myFixedArr = new MyFixedArray(1);                                                                                                                                          
$myFixedArray[] = 'foo';



Expected result:
----------------
array(1) {
  [0]=>
  NULL
}


Actual result:
--------------
array(3) {
  ["*foo"]=>
  NULL
  ["*bar"]=>
  NULL
  [0]=>
  NULL
}


*foo and *bar keys, can invoke troubles in some situations if You expects array 
without properties from inherited class. Method toArray should return values only 
for elements which are added to collection without properties inherited from 
class.