In these tests I've tried to test a lot of the corner cases
surrounding the addition of a `<type arguments>` selector to the
grammar (which we intend to do as part of constructor tearoffs), to
make sure that when we do so, we don't break any existing
functionality.
Change-Id: I765195cdd3745904f4aeb36663f59afe03381ab8
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/200001
Commit-Queue: Paul Berry <paulberry@google.com>
Reviewed-by: Lasse R.H. Nielsen <lrn@google.com>