yiisoft/yii2 — pull request #742 by cebe (2013-08-11 13:24:45+00:00)
Title: Fixed autoloader behavior according to leading \

As of PHP 5.3.2, PHP does not send class names with leading \ to
autoload functions.

Removed ltrim for '/' from autoload because it is

1. not needed: https://bugs.php.net/bug.php?id=50731 and
2. possibly wrong behavior: https://bugs.php.net/bug.php?id=51087