go/types, types2: better error msg when type inference fails in a call
In Checker.infer, report an error through an (incoming) *error_
so that the error can be reported as desired where infer is called.
Checker.infer is now a pure function.
Fixes #60543.
At call sites of Checker.infer, pass in an *error_ and use it to
report inference errors, together with additional information as
desired.
Fixes #60542.
In go/types, in error_.errorf, pass in a positioner rather than
a token.Pos. Also, introduce noposn, the positioner equivalent
for nopos. Adjust call sites as needed.
Change-Id: I462a7899a77a8bee2a21ba88299df237d74e0672
Reviewed-on: https://go-review.googlesource.com/c/go/+/558035 Reviewed-by: Robert Griesemer <gri@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Auto-Submit: Robert Griesemer <gri@google.com> Reviewed-by: Robert Findley <rfindley@google.com>