Description:
------------
'self' and 'parent' don't are evaluated when calling static member/method with class name in variables.

Reproduce code:
---------------
<?php

class foo {
  const foo = 1;
  public function __construct() {    
    $classname = 'parent';
    echo $classname::FOO;
    // Fatal error: Class 'parent' not found
    
    $classname = 'self';
    echo $classname::FOO;
    // Fatal error: Class 'self' not found 
    
    // new $classname; too
  }
}

new foo;

Actual result:
--------------
Fatal error: Class 'parent' not found

and

Fatal error: Class 'self' not found