Sema: fix sus overflow behavior in RangeSetUnhandledIterator
The old code assumed that `intAddScalar` could return a value outside
of the range of `ty`, which is problematic for many reasons.
The new code (ab)uses the InternPool for speed.
f673c98a7cJacob Young committed on 6/11/2023, 3:47:57 AM· committed by Andrew Kelleyparentd0cd1c8