self.oninstall = function(event) { ... };

self.oninstall = function(event) {
  event.waitUntil(
   caches.open('v1').then(function(cache) {
         return cache.add(
        '/sw-test/',
        '/sw-test/index.html',
        '/sw-test/style.css',
        '/sw-test/app.js',
        '/sw-test/image-list.js',
        '/sw-test/star-wars-logo.jpg',
        '/sw-test/gallery/',
        '/sw-test/gallery/bountyHunters.jpg',
        '/sw-test/gallery/myLittleVader.jpg',
        '/sw-test/gallery/snowTroopers.jpg'
     );
   })
   );
};