Issue 338 - Updated minimum version to Chrome 28 and got rid of legacy compatibility code

chrome/ext/background.js

 /*
  * This file is part of Adblock Plus <http://adblockplus.org/>,
  * Copyright (C) 2006-2014 Eyeo GmbH
  *
  * Adblock Plus is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 3 as
  * published by the Free Software Foundation.
  *
  * Adblock Plus is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with Adblock Plus.  If not, see <http://www.gnu.org/licenses/>.
  */
 
 (function()
 {
   /* Pages */
 
-  var sendMessage = chrome.tabs.sendMessage || chrome.tabs.sendRequest;
-
   var Page = ext.Page = function(tab)
   {
     this._id = tab.id;
     this._url = tab.url;
 
     this.browserAction = new BrowserAction(tab.id);
   };
   Page.prototype = {
     get url()
     {
@@ skipping 12 matching lines @@
         if (frame)
           return frame.url;
       }
     },
     activate: function()
     {
       chrome.tabs.update(this._id, {selected: true});
     },
     sendMessage: function(message, responseCallback)
     {
-      sendMessage(this._id, message, responseCallback);
+      chrome.tabs.sendMessage(this._id, message, responseCallback);
     }
   };
 
   ext.pages = {
     open: function(url, callback)
     {
       if (callback)
       {
         chrome.tabs.create({url: url}, function(openedTab)
         {
@@ skipping 243 matching lines @@
         return;
 
       chrome.contextMenus.removeAll();
       isContextMenuHidden = true;
     }
   };
 
 
   /* Message passing */
 
-  ext._setupMessageListener(function(sender)
+  chrome.runtime.onMessage.addListener(function(message, rawSender, sendResponse)
   {
-    return {
-      page: new Page(sender.tab),
+    var sender = {
+      page: new Page(rawSender.tab),
       frame: {
-        url: sender.url,
+        url: rawSender.url,
         get parent()
         {
-          var frames = framesOfTabs[sender.tab.id];
+          var frames = framesOfTabs[rawSender.tab.id];
 
           if (!frames)
             return null;
 
           for (var frameId in frames)
           {
-            if (frames[frameId].url == sender.url)
+            if (frames[frameId].url == rawSender.url)
               return frames[frameId].parent;
           }
 
           return frames[0];
         }
       }
     };
+
+    return ext.onMessage._dispatch(message, sender, sendResponse);
   });
 
 
   /* Storage */
 
   ext.storage = localStorage;
 })();