If an event is created as all day event, user can't modify it as it is : "Save" button is disabled in action bar.
The workaround is to disable "All day event", modify time value and check all day event one more time.
Steps To Reproduce
1) Create an "All day event" and save it
2) Edit and modify it (title, date, or whatever): you can't save (button Save disabled)
3) Uncheck "All day event", and modify start hour value : Save button is enabled.
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