Issue 4580 - Replace ext.devtools with devtools

ext/content.js

 /*
  * This file is part of Adblock Plus <https://adblockplus.org/>,
  * Copyright (C) 2006-present 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/>.
  */
 
 "use strict";
 
 (function()
 {
-  if (typeof ext == "undefined")
-    window.ext = {};
-
   let backgroundFrame = document.createElement("iframe");
   backgroundFrame.setAttribute("src",
                                "background.html" + window.location.search);
   backgroundFrame.style.display = "none";
   window.addEventListener("DOMContentLoaded", () =>
   {
     document.body.appendChild(backgroundFrame);
   });
-
-  let messageQueue = [];
-  let maxMessageId = -1;
-  let loadHandler = (event) =>
-  {
-    if (event.data.type == "backgroundPageLoaded")
-    {
-      let queue = messageQueue;
-      messageQueue = null;
-      if (queue)
-      {
-        for (let message of queue)
-          backgroundFrame.contentWindow.postMessage(message, "*");
-      }
-      window.removeEventListener("message", loadHandler);
-    }
-  };
-  window.addEventListener("message", loadHandler);
-
-  ext.backgroundPage = {
-    _sendRawMessage(message)
-    {
-      if (messageQueue)
-        messageQueue.push(message);
-      else
-        backgroundFrame.contentWindow.postMessage(message, "*");
-    }
-  };
-
-  /* Polyfills */
-
-  if (!("runtime" in browser))
-    browser.runtime = {};
-
-  browser.runtime.sendMessage = (message, responseCallback) =>
-  {
-    let messageId = ++maxMessageId;
-
-    ext.backgroundPage._sendRawMessage({
-      type: "message",
-      messageId,
-      payload: message
-    });
-
-    if (responseCallback)
-    {
-      let callbackWrapper = event =>
-      {
-        if (event.data.type == "response" && event.data.messageId == messageId)
-        {
-          window.removeEventListener("message", callbackWrapper);
-          responseCallback(event.data.payload);
-        }
-      };
-
-      window.addEventListener("message", callbackWrapper);
-    }
-  };
 }());