title: Service Workers not updating
body: <p>I have a service worker installed in my website, everything works fine, except when I push an update to the cached files, in fact; they stay catched forever and I seem to be unable to invalidate the cache unless I unsubscribe the worker from the `chrome://serviceworker-internals/</p>
  
  <pre><code>const STATIC_CACHE_NAME = 'static-cache-v1';
  const APP_CACHE_NAME = 'app-cache-#VERSION';
  
  const CACHE_APP = [
      '/',
      '/app/app.js'
  ]
  const CACHE_STATIC = [
      'https://fonts.googleapis.com/css?family=Roboto:400,300,500,700',
      'https://cdnjs.cloudflare.com/ajax/libs/normalize/4.1.1/normalize.min.css'
  ]
  
  self.addEventListener('install',function(e){
      e.waitUntil(
          Promise.all([caches.open(STATIC_CACHE_NAME),caches.open(APP_CACHE_NAME)]).then(function(storage){
              var static_cache = storage[0];
              var app_cache = storage[1];
              return Promise.all([static_cache.addAll(CACHE_STATIC),app_cache.addAll(CACHE_APP)]);
          })
      );
  });
  
  self.addEventListener('activate', function(e) {
      e.waitUntil(
          caches.keys().then(function(cacheNames) {
              return Promise.all(
                  cacheNames.map(function(cacheName) {
                      if (cacheName !== APP_CACHE_NAME &amp;&amp; cacheName !== STATIC_CACHE_NAME) {
                          console.log('deleting',cacheName);
                          return caches.delete(cacheName);
                      }
                  })
              );
          })
      );
  });
  
  self.addEventListener('fetch',function(e){
      const url = new URL(e.request.url);
      if (url.hostname === 'static.mysite.co' || url.hostname === 'cdnjs.cloudflare.com' || url.hostname === 'fonts.googleapis.com'){
          e.respondWith(
              caches.match(e.request).then(function(response){
                  if (response) {
                      return response;
                  }
                  var fetchRequest = e.request.clone();
  
                  return fetch(fetchRequest).then(function(response) {
                      if (!response || response.status !== 200 || response.type !== 'basic') {
                          return response;
                      }
                      var responseToCache = response.clone();
                      caches.open(STATIC_CACHE_NAME).then(function(cache) {
                          cache.put(e.request, responseToCache);
                      });
                      return response;
                  });
              })
          );
      } else if (CACHE_APP.indexOf(url.pathname) !== -1){
          e.respondWith(caches.match(e.request));
      }
  });
  </code></pre>
  
  <p>where #VERSION is a version that is appended to the cache name at compile time; note that STATIC_CACHE_NAME never changes, as the files are thought to be static forever.</p>
  
  <p>Also the behavior is erratic, I've been checking the delete function (the part where it logs) and it keeps logging about the deleting caches that have already been deleted (supposedly). when I run <code>caches.keys().then(function(k){console.log(k)})</code> I get a whole bunch of old caches that should've been removed.</p>