JSON parser was not rewritten when integers became fixed-size, so
some large integers could overflow silently and give the wrong
result, as could some doubles where the pre-decimal point digits
overflowed an `int`. Also added overflow protection for exponent.
Change-Id: I02941272c36fba4b9226e324936aebd4a5c5aa3b
Reviewed-on: https://dart-review.googlesource.com/c/91521
Commit-Queue: Lasse R.H. Nielsen <lrn@google.com>
Reviewed-by: Leaf Petersen <leafp@google.com>
Lasse R.H. Nielsen
671865cd1a