Issue 5315 - Add support for Microsoft Edge

ext/common.js

 /*
  * This file is part of Adblock Plus <https://adblockplus.org/>,
  * Copyright (C) 2006-2017 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()
 {
-  // Both Edge and Mozilla Web Extensions use
-  // the namespace 'browser' instead of 'chrome'
-  if (typeof browser != "undefined")
+  // Both Edge and Mozilla Web Extensions use the namespace
+  // 'browser' instead of 'chrome'. Edge has chrome namespace defined,
+  // in some cases, but only with one property: 'app'.
+  if (typeof chrome == "undefined" || typeof chrome.extension == "undefined")
     window.chrome = window.browser;

[Sebastian Noack, 2017/06/07 14:42:14]

Firefox actually has the "chrome" namespace as well, and we use it there, but it
has some minor inconsistencies with "browser". So this change would potentially
change behavior on Firefox.

At some point we should, use "browser" everywhere (and alias "chrome" to
"browser for Chrome). But for now, to keep this change as simple and as least
intrusive as possible, just check for the absence of "chrome" instead.

[Oleksandr, 2017/06/14 03:41:01]

There is actually a `chrome` object defined in Edge. It has only one property
'app' and nothing else. I don't know what it is for, but I think it wouldn't
hurt preserving it.

 
   window.ext = {};
 
   let EventTarget = ext._EventTarget = function()
   {
     this._listeners = new Set();
   };
   EventTarget.prototype = {
     addListener(listener)
     {
@@ skipping 37 matching lines @@
       return chrome.extension.getBackgroundPage();
     }
   };
 
 
   /* Utils */
 
   ext.getURL = chrome.extension.getURL;
   ext.i18n = chrome.i18n;
 }());