Global timezones are broken

[wrexroad]

Steps to reproduce

1. Create a new event by clicking a date on the calendar.
2. Click the "More" option.
3. Select UTC, GMT, or Z timezone.
4. Click "Create" (or "Update" for an existing event).

Expected behaviour

A new event with a global timezone should be created.

Actual behaviour

The creating the event fails silently and the sidebar does not close.

Server configuration

Operating system: Ubuntu 14.04 Web server: Apache Database: MySQL PHP version: 5.5.9 ownCloud version: (see ownCloud admin page) Nextcloud 9.0.53 (stable) Calendar version: (see ownCloud apps page) 1.3.1 (Also tested on GitHub master branch commit 8addb4). Updated from an older ownCloud or fresh install: Freshly built from GitHub repo. Signing status (ownCloud 9.0 and above):

No errors have been found.

Client configuration

Browser: Chrome Operating system: Fedora 24

[georgehrke]

fixed with #667

[georgehrke]

had to revert pr