This is the service worker

service-worker.js

var EXTRA_FILES = [
  "/xjs/_/js/k=xjs.ntp.en_US._WU8vYndmIc.O/m=jsa,ntp,d,csi/rt=j/d=1/t=zcms/rs=ACT90oH3VDY16AdrgBkBZukM4ZIP3OM-xQ",
];
var CHECKSUM = "e0n4rd";

var BLACKLIST = [
  '/gen_204\?',
  '/async/',
];

var FILES = [
  '/images/srpr/logo11w.png',
  '/images/srpr/chrome_ntp_white_logo2.png',
      '/' + '/ssl.gstatic.com/chrome/components/doodle-notifier-01.html'
].concat(EXTRA_FILES || []);

var CACHENAME = 'newtab-static-' + CHECKSUM;

self.addEventListener('install', function(event) {
  event.waitUntil(caches.open(CACHENAME).then(function(cache) {
    return cache.addAll(FILES);
  }));
});

self.addEventListener('activate', function(event) {
    return event.waitUntil(caches.keys().then(function(keys) {
    return Promise.all(keys.map(function(k) {
      if (k != CACHENAME && k.indexOf('newtab-static-') == 0) {
        return caches.delete(k);
      } else {
        return Promise.resolve();
      }
    }));
  }));
});

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

        return fetch(event.request).then(function(response) {
          var shouldCache = true;

          for (var i = 0; i < BLACKLIST.length; ++i) {
            var b = new RegExp(BLACKLIST[i]);
            if (b.test(event.request.url)) {
              shouldCache = false;
              break;
            }
          }

          if (event.request.method == 'POST') {
            shouldCache = false;
          }

                    if (shouldCache) {
            return caches.open(CACHENAME).then(function(cache) {
              cache.put(event.request, response.clone());
              return response;
            });
          } else {
            return response;
          }
        });
      })
  );
});



if (!Cache.prototype.add) {
  
  Cache.prototype.add = function add(request) {
        return this.addAll([request]);
  };
}

if (!Cache.prototype.addAll) {
  
  Cache.prototype.addAll = function addAll(requests) {
        var cache = this;

        function NetworkError(message) {
      this.name = 'NetworkError';
      this.code = 19;
      this.message = message;
    }
    NetworkError.prototype = Object.create(Error.prototype);

    return Promise.resolve().then(function() {
      if (arguments.length < 1) throw new TypeError();

            var sequence = [];

      requests = requests.map(function(request) {
        if (request instanceof Request) {
          return request;
        }
        else {
          return String(request);          }
      });

      return Promise.all(
          requests.map(function(request) {
            if (typeof request === 'string') {
              request = new Request(request);
            }

            return fetch(request.clone());
          })
      );
    }).then(function(responses) {
                  return Promise.all(
          responses.map(function(response, i) {
            return cache.put(requests[i], response);
          })
      );
    }).then(function() {
      return undefined;
    });
  };
}

if (!CacheStorage.prototype.match) {
    
  CacheStorage.prototype.match = function match(request, opts) {
    var caches = this;
    return caches.keys().then(function(cacheNames) {
      var match;
      return cacheNames.reduce(function(chain, cacheName) {
        return chain.then(function() {
          return match || caches.open(cacheName).then(function(cache) {
            return cache.match(request, opts);
          }).then(function(response) {
            match = response;
            return match;
          });
        });
      }, Promise.resolve());
    });
  };
}