e5cf5d9502
Previously, all boxed native field slots were marked not nullable. However, several boxed native fields are in fact nullable, which means that even generated IL that appropriately checks these fields for null can break in optimized code when the null checks are removed. Also add some helper utilities for working with representations. Change-Id: I22703d14cfbadbabeae74179476dea47ace12161 Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/159280 Commit-Queue: Tess Strickland <sstrickl@google.com> Reviewed-by: Ryan Macnak <rmacnak@google.com> Reviewed-by: Clement Skau <cskau@google.com>