如何在Polymer Starter Kit的Service Worker文件中导入另一个Javascript文件

self.addEventListener('install', function(event) {
  event.waitUntil(
    caches.open('my-cache').then(function(cache) {
      return cache.addAll([
        '/path/to/your/javascript/file.js'
      ]);
    })
  );
});

self.addEventListener('fetch', function(event) {
  event.respondWith(
    caches.match(event.request).then(function(response) {
      return response || fetch(event.request);
    })
  );
});

<script>
  if ('serviceWorker' in navigator) {
    window.addEventListener('load', function() {
      navigator.serviceWorker.register('/path/to/your/service-worker.js');
    });
  }
</script>