I used a script to "unroll" some of the calls to
TemporalHelpers.checkToTemporalCalendarFastPath(), and rewrite it slightly
not to use a specific Calendar instance. This is in preparation for a
future refactor, but also allows testing the PlainTime path which was not
previously covered.
(I didn't unroll all the calls and remove the helper yet, because the
remaining calls have custom assertions that I haven't gotten the script to
work with yet. For the same reason, I didn't yet convert these to use the
test generation facility. These will follow in a future PR.)
a157570ddc