Update internal change-of-date alarm whenever timezone changes

We weren't updating the next-midnight alarm when the device time
zone was changed, meaning that the date-change broadcast did not
happen appropriately.

Bug: 117577062
Test: manual
Test: atest CtsAlarmManagerTestCases
Change-Id: I8d565f5c7da58a99e984b11d7745698e15bf47ef
1 file changed