Revert "Fixed an issue when a phar file is used in "files" option in composer.json"
This reverts commit 41e91f3064cee51dd52f45831dc48748ce37a095.
The commit 41e91f3 in current codebase generates absolute path in
autoload_static.php for phar file.
Also according to http://php.net/manual/en/phar.using.intro.php, the `phar://`
prefix is not needed.