DatePicker crashes when going from 2036 to 2035 via ▼

1. Some obsolte logic was placing invalid index in the array of
   scroll wheel items which was resulting in failure to look its
   string representation from the cache causing a NPE.

2. While editing the current value via the IME the middle item
   of the scroll wheel was partially visible i.e. the user was
   able to see a dimmed version of the old value intermixed with
   the new one.

3. The logic for hiding the IME while poking a button i.e. starting
   to use another way of changing the current value, was incorrect.

bug:5480205

Change-Id: I1c2c96402bd38bac1dec64ccc6b550410332b9d7