Convert the RSS extension to event pages to avoid a dedicated background process.

chrome/test/data/extensions/subscribe_page_action/popup.js

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 function feedLink(url) {
   var feed_link = document.createElement('a');
   feed_link.href = url;
   feed_link.addEventListener("click", onClick);
   return feed_link;
 }
 
 function main() {
   chrome.tabs.getSelected(null, function(tab) {
-    var feeds = chrome.extension.getBackgroundPage().feedData[tab.id];
+    var feeds = JSON.parse(localStorage.getItem(tab.id));

[not at google - send to devlin, 2013/03/28 00:35:05]

I don't fully understand what this is for, but we're encouraging the storage API
over localstorage - and this will be especially useful if it makes sense for
this to be sync'd.

     if (feeds.length == 1) {
       // Only one feed, no need for a bubble; go straight to the subscribe page.
       preview(feeds[0].href);
     } else {
       var content = document.getElementById('content');
       var heading = document.getElementById('heading');
       heading.innerText =
           chrome.i18n.getMessage("rss_subscription_action_title");
       content.appendChild(document.createElement('br'));
 
@@ skipping 42 matching lines @@
   } else {
     // Show the preview page.
     url = "subscribe.html?" + encodeURIComponent(feed_url);
   }
   chrome.tabs.create({ url: url });
   window.close();
 }
 
 // Init on DOM ready.
 document.addEventListener('DOMContentLoaded', main);