Before this commit:
1. The date would be displayed as UTC regardless of the user timezone.
2. The date would be sent to the backend in the browser timezone
Now we correctly take the user timezone into consideration when handling date.
Step to reproduce:
- Install a second language where time format is: %H.%M.%S or %H,%M,%S
(eg: Finnish, Bulgarian, Albanian )
- Set it as website default's language
- Open page properties dialog on any page
- The date looks correctly displayed but it is in fact the UTC hour and not
the user timezone date. (eg: 2 hours missing in Albanian case, it would
show '2018-Pri-05 02.11.02.' instead of '2018-Pri-05 04.11.02.')
- If you save, it will crash since it will send the wrong date format to the
backend that is expecting 'YYYY-MM-DD HH:MM:SS' format.
Closes#23500, closes#23566