Description:
------------
After creating a MongoDate() using a date prior to the negative 32bit unix epoch (before Dec 13 1901), unexpected results unless specifically call setTimezone() on the resulting DateTime() object.

Behavior began in PHP-5.5.25 and confirmed in PHP-5.5.26, confirms as expected in PHP-5.5.24.

Test script:
---------------
date_default_timezone_set('America/New_York');

$dateString = '1900-01-01 12:20:00';

$dateTime = new \DateTime($dateString);
var_dump($dateTime);

$mongoDateTime = new MongoDate(strtotime($dateString));

$dateTimeTest = $mongoDateTime->toDateTime();
var_dump($dateTimeTest);

// to get expected result
$dateTimeTest->setTimezone(new DateTimeZone('America/New_York'));  
echo "timezone after set...\n";  
var_dump($dateTimeTest);  

Expected result:
----------------
class DateTime#1 (3) {
  public $date =>
  string(26) "1900-01-01 12:20:00.000000"
  public $timezone_type =>
  int(3)
  public $timezone =>
  string(16) "America/New_York"
}
class DateTime#3 (3) {
  public $date =>
  string(26) "1900-01-01 17:20:00.000000"
  public $timezone_type =>
  int(1)
  public $timezone =>
  string(6) "+00:00"
}
timezone after set...
class DateTime#3 (3) {
  public $date =>
  string(26) "1900-01-01 12:20:00.000000"
  public $timezone_type =>
  int(3)
  public $timezone =>
  string(16) "America/New_York"
}


Actual result:
--------------
class DateTime#1 (3) {
  public $date =>
  string(26) "1900-01-01 12:20:00.000000"
  public $timezone_type =>
  int(3)
  public $timezone =>
  string(16) "America/New_York"
}
class DateTime#3 (3) {
  public $date =>
  string(26) "1900-01-01 17:16:02.000000"
  public $timezone_type =>
  int(1)
  public $timezone =>
  string(6) "+00:00"
}
timezone after set...
class DateTime#3 (3) {
  public $date =>
  string(26) "1900-01-01 12:20:00.000000"
  public $timezone_type =>
  int(3)
  public $timezone =>
  string(16) "America/New_York"
}