Description:
------------
When a base class implements an interface the base class is also threated as an interface. IT'S A CRITICAL BUG IN MY OPINION!!!



Reproduce code:
---------------
<?php 
error_reporting( E_ALL ); 
set_error_handler('errorReporting'); 

interface test { } 

class ParentClass 
implements test 
{ 
    private function foo() { } 
} 

class ChildClass 
extends ParentClass 
{ 
    //HERE WE GET AN STRICT ERROR BECAUSE OF THE PARAMS BUT THE FUNCTION IS NOT DEFINED IN THE INTERFACE OR ABSTRACT
    public function foo(array $content) { } 
} 

function errorReporting($errno, $errstr, $errfile, $errline) 
{ 
    echo($errstr); 
} 
?> 

Expected result:
----------------
no erros

Actual result:
--------------
We get a strict error here