Fix up scanner

Change-Id: I862677f35266c253c8206742d02651ffe632f47d
diff --git a/go/src/v.io/x/ref/services/discovery/scanner/scanner.go b/go/src/v.io/x/ref/services/discovery/scanner/scanner.go
index c28fa3d..65745d7 100644
--- a/go/src/v.io/x/ref/services/discovery/scanner/scanner.go
+++ b/go/src/v.io/x/ref/services/discovery/scanner/scanner.go
@@ -14,13 +14,13 @@
 
 type responseHandler struct{}
 
-func (r *responseHandler) Add(s ble.Service) error {
-	log.Println("Found:", s)
+func (r *responseHandler) Found(a ble.Advertisement) error {
+	log.Println("Found:", a)
 	return nil
 }
 
-func (r *responseHandler) Remove(s ble.Service) error {
-	log.Println("Removed:", s)
+func (r *responseHandler) Lost(a ble.Advertisement) error {
+	log.Println("Removed:", a)
 	return nil
 }