Remove relevant console log,

src/firebase-messaging-sw.js

@@ -1,9 +1,7 @@
  if ('serviceWorker' in navigator) {
     navigator.serviceWorker.register('./firebase-messaging-sw.js')
       .then(function(registration) {
-        console.log('Registration successful, scope is:', registration.scope);
       }).catch(function(err) {
-        console.log('Service worker registration failed, error:', err);
       });
     } 
 // Scripts for firebase and firebase messaging