The calendar import from office 365 incorrectly imports whole day events by applying the Timezone offset to an ICS file that already contains a time zone offset.

Steps to reproduce:

In Outlook / Office 365:

1. Create a calendar in office 365 using a timezone with a negative offset (such as America/New York)
2. Create a whole day event in the outlook calendar

In Moodle:

1. In Moodle set the server timezone to America/New York (or match the timezone used in step 1 above)
2. Make sure that the user logging into Moodle has their profile set to the same time zone as the server
3. Navigate into Any course.
4. Import the calendar into a Moodle course as a course event (Use the URL and subscribe to office 365 calendar link)
5. View the calendar in Moodle as the user and compare to the Office 365 calendar

Expected result:
the calendars should match

Actual result:
The events are displayed the day before in the evening. Moodle applies the timezone offset incorrectly so for a timezone of New York, the event may be listed at either 7PM or 8PM the night before depending on DST

The only way to get the events to display correctly is for the user to view them using UTC (which will skew all of their other dates)