eb17dad604
Allows CHA to notice `length` and `[]` have a single target the receiver is a mutable or immutable array. TEST=ci Bug: https://github.com/dart-lang/sdk/issues/48361 Change-Id: I9e3ecabab1d32a4baa6e635cd660184ed9bb8fb1 Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/232425 Reviewed-by: Daco Harkes <dacoharkes@google.com> Commit-Queue: Ryan Macnak <rmacnak@google.com>