Fix crash in new time zone picker.

When entering the new time zone picker with a fixed offset time zone
(such as UTC) selected, it would crash with a NullPointerException.

This fixes the crash.

Bug: 72143165
Bug: 62255208
Test: manual
Change-Id: I1f54d3276edb98ab7bd6a092be4497386a69d6be
1 file changed