ab30452db5
These changes are also being back ported into the existing SDK with minimal differences that will be gone when we unfork the dart:_runtime library. In the current back port: * FutureOr<Null>? is normalized to Future<Null>* instead of Future<Null>?. * There is no runtime normalization of FutureOr<T?>?. This should have no effect since nullable types can not yet appear. Fixes: #40611, #40720 Change-Id: Ib3ddffbf3778f0f571cf95f58b6142d3ee0bf59b Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/136160 Reviewed-by: Sigmund Cherem <sigmund@google.com> Reviewed-by: Mark Zhou <markzipan@google.com> Commit-Queue: Nicholas Shahan <nshahan@google.com>