Description:
------------
When creating a new DateTimeZone with an invalid tz name, the documentation states that it will emit an exception.

This happens, however.. a notice is also emitted, although not immediately visible. This notice pops its head up when calling error_get_last().

Test script:
---------------
php -d error_reporting=-1 -d display_errors=1  -r ' try { @new DateTimeZone("YOUR MOM"); } catch (Exception $e) {} print_r( error_get_last() ); ';

Expected result:
----------------
NULL

Actual result:
--------------
Array
(
    [type] => 2
    [message] => DateTimeZone::__construct(): Unknown or bad timezone (YOUR MOM)
    [file] => Command line code
    [line] => 1
)