8baa649665
With the new class hierarchy builder and mixin stubs we no longer insert superfluous forwarding stub nor use mixin declaration/clones as targets inconsistently. These test expand upon existing tests to verify that these issue have been fixed. Change-Id: I27db6e27e86d8c83692e9a16f7c435f633a599c3 Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/194787 Reviewed-by: Jens Johansen <jensj@google.com> Commit-Queue: Johnni Winther <johnniwinther@google.com>