ccb16f7282
turn on strong mode and sync-async on by default. Change-Id: I1e9d656bce7bb99b6a41110458604514a1717d0f Reviewed-on: https://dart-review.googlesource.com/71020 Reviewed-by: Alexander Aprelev <aam@google.com> Commit-Queue: Siva Annamalai <asiva@google.com>