go/types, types2: remove unused code in lookupFieldOrMethod
The underlying type of a type parameter is an interface,
so we don't need a special case for type parameters anymore.
Simply share the (identical) code for interfaces.
Adjust code in types.NewMethodSet accordingly.
No functional difference.
Preparation for fix of issues below.
For #50233.
For #50417.
Change-Id: Ib2deadd12f89e6918dec224b4ce35583001c3101
Reviewed-on: https://go-review.googlesource.com/c/go/+/375514
Trust: Robert Griesemer <gri@golang.org>
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org> Reviewed-by: Robert Findley <rfindley@google.com>