63918ea921
Eliminate uses of the comment syntax in lib/async. This is mostly done simply by turning explicit (but commented) casts into implicit casts to avoid regressing dart2js performance. Bug: Change-Id: I286c7bffbf609b5e2fa24b9d48b90876c2c45a9b Reviewed-on: https://dart-review.googlesource.com/21566 Reviewed-by: Paul Berry <paulberry@google.com> Reviewed-by: Stephen Adams <sra@google.com>