As suggested in #1893800-47: Something is very, very wrong with update.php / upgrade tests... demons suspected I filed separate issue
I got random number of failed upgrade tests in http://qa.drupal.org/pifr/test/443928
Suppose this random failures are caused by undocumented usage of displays in upgrade from #1852966-126: Rework entity display settings around EntityDisplay config entity but not sure
The number of failed upgrade tests that fails are always different also I can't reproduce it locally in PHP 5.3.14