All Day cannot span multiple days after update to 7.x-2.11

Problem/Motivation

After updating to 7.x-2.11, checking the "all day" on a date field no longer works as expected. If "All Day" is selected and the content is saved, if you go back to that content's edit page "All Day" will go back to being unchecked, the ending date changes to match the start date, and the start time is shown as 12:00am and end time as 11:55pm.

Steps to reproduce

1. Create a content type with a date field with the following settings
   • required field
   • unlimited number of values
   • check year, month, day, hour, minute
   • check collect an end date
   • under time zone handling select "Date's time zone"
   • under repeating date select "yes"
2. Add content, select staring and ending dates, check "All Day"
3. Save
4. See how date has changed on the content's page as well as its edit page