types/dnstype: use viewer instead of cloner

This was missed when I did the initial viewer work.

Signed-off-by: Maisem Ali <maisem@tailscale.com>

types/dnstype/dnstype.go

@@ -5,7 +5,7 @@
 // Package dnstype defines types for working with DNS.
 package dnstype
 
-//go:generate go run tailscale.com/cmd/cloner --type=Resolver --clonefunc=true
+//go:generate go run tailscale.com/cmd/viewer --type=Resolver --clonefunc=true
 
 import (
 	"net/netip"

types/dnstype/dnstype_view.go

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// Code generated by tailscale.com/util/codegen (viewer); DO NOT EDIT.
+// Code generated by tailscale/cmd/viewer; DO NOT EDIT.
 
 package dnstype
 
@@ -15,14 +15,18 @@ import (
 )
 
 //go:generate go run tailscale.com/cmd/cloner  -clonefunc=true -type=Resolver
+
 // View returns a readonly view of Resolver.
 func (p *Resolver) View() ResolverView {
 	return ResolverView{ж: p}
 }
 
-// ResolverView provides a read-only view on Resolver.
-// It's methods should only be called if `Valid()` returns true.
+// ResolverView provides a read-only view over Resolver.
+//
+// Its methods should only be called if `Valid()` returns true.
 type ResolverView struct {
+	// ж is the underlying mutable value, named with a hard-to-type
+	// character that looks pointy like a pointer.
 	// It is named distinctively to make you think of how dangerous it is to escape
 	// to callers. You must not let callers be able to mutate it.
 	ж *Resolver
@@ -34,7 +38,7 @@ func (v ResolverView) Valid() bool { return v.ж != nil }
 // AsStruct returns a clone of the underlying value which aliases no memory with
 // the original.
 func (v ResolverView) AsStruct() *Resolver {
-	if v.ж != nil {
+	if v.ж == nil {
 		return nil
 	}
 	return v.ж.Clone()