control/controlclient: make Status.Persist a PersistView

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

ipn/ipnlocal/local.go

@@ -818,10 +818,10 @@ func (b *LocalBackend) setClientStatus(st controlclient.Status) {
 		prefs.ControlURL = prefs.ControlURLOrDefault()
 		prefsChanged = true
 	}
-	if st.Persist != nil {
-		if !prefs.Persist.Equals(st.Persist) {
+	if st.Persist != nil && st.Persist.Valid() {
+		if !prefs.Persist.View().Equals(*st.Persist) {
 			prefsChanged = true
-			prefs.Persist = st.Persist.Clone()
+			prefs.Persist = st.Persist.AsStruct()
 		}
 	}
 	if st.URL != "" {

ipn/ipnlocal/state_test.go

@@ -139,10 +139,11 @@ func (cc *mockControl) populateKeys() (newKeys bool) {
 // (In our tests here, upstream is the ipnlocal.Local instance.)
 func (cc *mockControl) send(err error, url string, loginFinished bool, nm *netmap.NetworkMap) {
 	if cc.statusFunc != nil {
+		pv := cc.persist.View()
 		s := controlclient.Status{
 			URL:     url,
 			NetMap:  nm,
-			Persist: cc.persist,
+			Persist: &pv,
 			Err:     err,
 		}
 		if loginFinished {