Issue 5027 - Use updated webRequest API for WebSocket blocking

lib/requestBlocker.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
@@ skipping 134 matching lines @@
 
 FilterNotifier.on("subscription.added", onFilterChange);
 FilterNotifier.on("subscription.removed", onFilterChange);
 FilterNotifier.on("subscription.updated", onFilterChange);
 FilterNotifier.on("subscription.disabled", arg => onFilterChange(arg, true));
 FilterNotifier.on("filter.added", onFilterChange);
 FilterNotifier.on("filter.removed", onFilterChange);
 FilterNotifier.on("filter.disabled", arg => onFilterChange(arg, true));
 FilterNotifier.on("load", onFilterChange);
 
-
-// Versions of Chrome < 58 do not support WebSockets since the release of

[Sebastian Noack, 2017/03/28 13:48:08]

On Chrome <58, the webRequest API doesn't intercept WebSocket connections, see
https://crbug.com/129353. Hence we patched the WebSocket object as a workaround.
WebSocket connections detected by this workaround are handled below.

[Jon Sonesen, 2017/03/28 19:18:30]

Sorry, thank you for clarifying the comments here.

-// the 58 beta we are using this check to disable the CSP injection workaround.
-//
-// SharedWorkers will not be blocked by this workaround being disabled a

[Sebastian Noack, 2017/03/28 13:48:08]

WebSocket connections opened by SharedWorkers are not blocked, due to
https://crbug.com/705931. On Chrome <58, however, those are covered by the
workaround in lib/csp.js.

[Sebastian Noack, 2017/03/28 14:33:44]

Nevermind. This paragraph should rather just go away. The new Chrome bug you
filed is off-topic, and pointing it out here is rather confusing. 

[Jon Sonesen, 2017/03/28 19:18:30]

Acknowledged.

-// fix would be if the browser associated the SharedWorker tabId/frameId with
-// the document that caused it to be created.
-//
-// Chromium ticket has been filed: https://crbug.com/705931
-if (("WEBSOCKET" in chrome.webRequest.ResourceType))
+// Before Chrome 58, the webRequest API didn't intercept WebSocket connections,
+// (see https://crbug.com/129353). Hence we patched the WebSocket object as a
+// workaround. WebSocket connections detected by this workaround are handled
+// below.
+if (!("WEBSOCKET" in chrome.webRequest.ResourceType))
 {
   port.on("request.websocket", (msg, sender) =>
   {
     return ext.webRequest.onBeforeRequest._dispatch(
       new URL(msg.url),
       "WEBSOCKET",
       sender.page,
       sender.frame
     ).indexOf(false) != -1;
   });
 }