Stephen Adams
90bba41618
`o is T` where `T` is an interface implemented by a class hierarchy can be implemented as `o instanceof R` where `R` is the root of the hierarchy. The common case is that `R` is a single implementation class. `is Record` and `is Type` now generally use `instanceof`. Fixes: #51366 Change-Id: I1943533bc53024f3199f71910034d49cf6661b22 Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/294320 Commit-Queue: Stephen Adams <sra@google.com> Reviewed-by: Mayank Patke <fishythefish@google.com>