Clean up VCALENDAR/TIME_ZONE_INFORMATION code

* Fix the transition times so that they occur at the hour
* Remove an unused variable
* Fix a reference to Calendar.HOUR that should have been
  Calendar.HOUR_OF_DAY
* Confirm that unit tests work properly

Change-Id: I3eaf31d160e97b5f3ba59c83878359085aea960d
2 files changed