var cacheName = 'tempConverterShell';var filesToCache = ['/','/index.html','/scripts/sumple.js','/styles/sumple.css'];self.addEventListener('install', function(event) {  console.log('ServiceWorker installing');event.waitUntil(    caches.open(cacheName).then(function(cache) {      console.log('Service Worker caching app shell');return cache.addAll(filesToCache);    })  );});self.addEventListener('activate', function(event) {  console.log('Service Worker activating');event.waitUntil(    caches.keys().then(function(keyList) {returnPromise.all(keyList.map(function(key) {if (key !== cacheName) {          console.log('Service Worker removing old cache', key);return caches.delete(key);        }      }));    })  );returnself.clients.claim();});self.addEventListener('fetch', function(event) {  console.log('Service Worker fetching ', event.request.url);event.respondWith(caches.match(event.request).then(function(response) {return response || fetch(event.request);    })  );});