Description:
------------
---versions---
5.6.25、7.0.6

---Description---
public static DateTime DateTime::createFromFormat ( string $format , string $time [, DateTimeZone $timezone = date_default_timezone_get() ] )

When format option contain a microsecond string like 'U.u', the tiemzone option is invalid. 


Test script:
---------------
<?php
$timezone = new \DateTimeZone('PRC'); 
$now = DateTime::createFromFormat('U.u', number_format(microtime(true), 6, '.', ''), $timezone);
print_r($now);
$now->setTimezone($timezone);
print_r($now);
?>

Expected result:
----------------
two results should be equal

Actual result:
--------------
Two results are not equal

DateTime Object
(
    [date] => 2016-09-13 15:55:50.946395
    [timezone_type] => 1
    [timezone] => +00:00
)
DateTime Object
(
    [date] => 2016-09-13 23:55:50.946395
    [timezone_type] => 3
    [timezone] => PRC
)