Gaunt Face | Matt Gaunt - Push Notifications & Service Worker
https://gauntface.com/blog/2014/12/15/push-notifications-service-worker
https://github.com/gauntface/simple-push-demo
https://simple-push-demo.appspot.com/
Google Cloud Messaging for Chrome(Google)
http://developer.chrome.com/apps/cloudMessaging.html
Building efficient apps and extensions with push messaging (Google Developers Blog)
http://googledevelopers.blogspot.jp/2013/05/building-efficient-apps-and-extensions.html