Description:
------------
E_RECOVERABLE_ERROR halts the interpreter. While shutdown_function is called, one cannot handle framework shutdown, responses, and logging in an appropriate manner.

E_RECOVERABLE_ERROR should be catchable by a `catch( Throwable $t)` or `catch(ERROR $e)`, and finally blocks _must_ be executed.

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

$x = new stdClass();
try {
	echo $x;
} catch (Throwable $t) {
	echo "Yeah, we couldn't convert that to a string. Log error and respond to client's request";
	echo $t->__toString();
} finally {
	echo "Seriously? I must be wrong";
}

Expected result:
----------------
Something like:
Yeah, we couldn't convert that to a string. Log error and respond to client's request.

E_RECOVERABLE_ERROR: Object of class stdClass could not be converted to string

Seriously? I must be wrong



Actual result:
--------------
PHP Catchable fatal error:  Object of class stdClass could not be converted to string in /tmp/foo.php on line 5
PHP Stack trace:
PHP   1. {main}() /tmp/foo.php:0

Catchable fatal error: Object of class stdClass could not be converted to string in /tmp/foo.php on line 5