[php-src] Issue #10411: IntlCalendar/intlDateFormatere calculate wrongly the calendar-transformation gregorian->islamic ->gregorian and others

Issue: https://github.com/php/php-src/issues/10411 Author: porthd ### Description I tested the following code on a phpsandbox (https://onlinephp.io/) The code will transform a gregorian Datetime into a islamic datetime. After that the islamice datetime will be transformed into a gregorian datetime. I would expect the original datetime. I got something else. I used the code from the link https://stackoverflow.com/questions/24042819/converting-non-gregorian-dates-using-intldateformatter for this example. A similar problem happens with the calendar chinese od buddhist. I have not tested the other calendars. Even if you use the calendar gregorian, I will get wrong results. Perhaps I read the documentation in the wrong way. The following code: ```php[ <?php $calendar = 'islamic'; $fmt = new IntlDateFormatter( 'de_DE@calendar=gregorian', IntlDateFormatter::SHORT, //date format IntlDateFormatter::SHORT, //time format 'Europe/Berlin', IntlDateFormatter::TRADITIONAL ); // $fmt->setPattern('MM-dd-YYYY HH:mm:ss'); $time = $fmt->parse('09/13/2022 13:46'); echo('tstamp: '.$time."\n"); $formatter = IntlDateFormatter::create("de_DE@calendar=".$calendar, IntlDateFormatter::SHORT, IntlDateFormatter::SHORT, 'Europe/Berlin', IntlDateFormatter::TRADITIONAL); // $formatter->setPattern('MM-dd-YYYY HH:mm:ss'); echo ($help = $formatter->format($time)."\n"); $list = explode(' ',$help); $fmt = new IntlDateFormatter( 'de_DE@calendar='.$calendar, IntlDateFormatter::SHORT, //date format IntlDateFormatter::SHORT, //time format 'Europe/Berlin', IntlDateFormatter::TRADITIONAL ); // $fmt->setPattern('MM-dd-YYYY HH:mm:ss'); $time = $fmt->parse($help); echo('tstamp: '.$time."\n"); $formatter = IntlDateFormatter::create("de_DE@calendar=gregorian", IntlDateFormatter::SHORT, IntlDateFormatter::SHORT, 'Europe/Berlin', IntlDateFormatter::GREGORIAN ); // $formatter->setPattern('MM-dd-YYYY HH:mm:ss'); echo ($help = $formatter->format($time)."\n".'This should be 09/13/22 13:46'); ``` Resulted in this output: ``` tstamp: 1673268360 17.6.1444 AH 13:46 tstamp: 1673268360 09.01.23 13:46 This should be 09/13/22 13:46 ``` But I expected this output instead: ``` 17.6.1444 AH 13:46 tstamp: 1673268360 09/13/22 13:46 This should be 09/13/22 13:46 ``` ### PHP Version php 7.4.21; php 8.0.27, php 8.1.14, php 8.2.1 ### Operating System _No response_