c49560cd37
Also make NBitMask generic, replace uses of SignedNBitMask with generic NBitMask, and remove SignedNBitMask. TEST=No changes to functionality for existing callers, so existing tests. Cq-Include-Trybots: luci.dart.try:vm-kernel-linux-release-simarm-try,vm-kernel-linux-release-simarm64-try,vm-kernel-precomp-linux-release-simarm-try,vm-kernel-precomp-linux-release-simarm64-try Change-Id: Ic33785e50be98123c75782c6e62ef32ec45f4191 Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/208181 Commit-Queue: Tess Strickland <sstrickl@google.com> Reviewed-by: Daco Harkes <dacoharkes@google.com>