Description:
------------
Iterating over a dateperiod twice does not "reset" the iterator,
but starts the second iteration at the endate.

This is kindof an duplicate of #46874, but Derick asked me to add it anyways.

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

$start    = new DateTime('20101212');
$interval = DateInterval::createFromDateString('next day');
$dp = new DatePeriod($start, $interval, 0);
foreach($dp as $dt) {
    echo $dt->format('r') . "\n"; // Sun, 12 Dec 2010 00:00:00 +0100
}
foreach($dp as $dt) {
    echo $dt->format('r') . "\n"; // Mon, 13 Dec 2010 00:00:00 +0100
}

Expected result:
----------------
Sun, 12 Dec 2010 00:00:00 +0100
Sun, 12 Dec 2010 00:00:00 +0100

Actual result:
--------------
Sun, 12 Dec 2010 00:00:00 +0100
Mon, 13 Dec 2010 00:00:00 +0100