go/types, types2: rename Named.under to Named.resolveUnderlying
Named.resolveUnderlying is now just a helper function for Underlying
and only called from there. The name makes is clearer what this function
does; it also doesn't need to return a result anymore.
While at it, slightly simplify the function body.
Change-Id: I167c4be89b1bfcc69f6b528ddb6ed4c90481194a
Reviewed-on: https://go-review.googlesource.com/c/go/+/712521
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Mark Freeman <markfreeman@google.com>
Auto-Submit: Robert Griesemer <gri@google.com> Reviewed-by: Robert Griesemer <gri@google.com>