TEST=augmented few existing tests Bug: https://github.com/dart-lang/sdk/issues/52121 CoreLibraryReviewExempt: VM-only change, other platforms don't support this API. Change-Id: I95decae6cf1a5c6ad694747313aa0dbe0a13025d Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/312981 Reviewed-by: Lasse Nielsen <lrn@google.com> Commit-Queue: Slava Egorov <vegorov@google.com> Reviewed-by: Martin Kustermann <kustermann@google.com>
