Description:
------------
When a fatal error is throwed in a callback used with 
register_shutdown_function(), php exit code is 0 instead of 255.
There is no problem with PHP < 5.4

Test script:
---------------
<?php

register_shutdown_function(function()
		{
			require 'path/to/an/unknown/file';
		}
);

Expected result:
----------------
# php testScript.php
# echo $?
255

Actual result:
--------------
# php testScript.php
# echo $?
0