Added string quotes on default of optional parameter for SplFileInfo::openFile()

git-svn-id: https://svn.php.net/repository/phpdoc/en/trunk@333314 c90b9560-bf6c-de11-be94-00142212c4b1
Change double quotes to single based on https://github.com/php/php-src/blob/master/ext/spl/spl.php#L973

git-svn-id: https://svn.php.net/repository/phpdoc/en/trunk@333315 c90b9560-bf6c-de11-be94-00142212c4b1