0828d2c786
Set literals have an exact type of Set<T> for some T. An implicit downcast to a subtype is a static error. Change-Id: I922b078b1b9e595243520e73c7130c23fe91f454 Reviewed-on: https://dart-review.googlesource.com/c/91640 Commit-Queue: Kevin Millikin <kmillikin@google.com> Reviewed-by: Dmitry Stefantsov <dmitryas@google.com> Reviewed-by: Aske Simon Christensen <askesc@google.com>