Issue 4364 - Drop support for Chrome 29-40 and remove legacy code

include.preload.js

Index: include.preload.js
===================================================================
--- a/include.preload.js
+++ b/include.preload.js
@@ -196,9 +196,8 @@
   }
 }
 
-function ElementHidingTracer(document, selectors)
+function ElementHidingTracer(selectors)
 {
-  this.document = document;
   this.selectors = selectors;
 
   this.changedNodes = [];
@@ -264,7 +263,7 @@
     // Forget previously changed nodes that are no longer in the DOM.
     for (var i = 0; i < this.changedNodes.length; i++)
     {
-      if (!this.document.contains(this.changedNodes[i]))
+      if (!document.contains(this.changedNodes[i]))
         this.changedNodes.splice(i--, 1);
     }
 
@@ -274,7 +273,7 @@
       var node = mutation.target;
 
       // Ignore mutations of nodes that aren't in the DOM anymore.
-      if (!this.document.contains(node))
+      if (!document.contains(node))
         continue;
 
       // Since querySelectorAll() doesn't consider the root itself
@@ -317,10 +316,10 @@
 
   trace: function()
   {
-    this.checkNodes([this.document]);
+    this.checkNodes([document]);
 
     this.observer.observe(
-      this.document,
+      document,
       {
         childList: true,
         attributes: true,
@@ -331,13 +330,13 @@
 
   disconnect: function()
   {
-    this.document.removeEventListener("DOMContentLoaded", this.trace);
+    document.removeEventListener("DOMContentLoaded", this.trace);
     this.observer.disconnect();
     clearTimeout(this.timeout);
   }
 };
 
-function runInDocument(document, fn, arg)
+function runInDocument(fn, arg)
 {
   var script = document.createElement("script");
   script.type = "application/javascript";
@@ -352,7 +351,7 @@
 // us. As a workaround we wrap WebSocket, preventing blocked WebSocket
 // connections from being opened.
 // [1] - https://bugs.chromium.org/p/chromium/issues/detail?id=129353
-function wrapWebSocket(document)
+function wrapWebSocket()
 {
   if (typeof WebSocket == "undefined")
     return;
@@ -372,7 +371,7 @@
     });
   });
 
-  runInDocument(document, function(eventName)
+  runInDocument(function(eventName)
   {
     // As far as possible we must track everything we use that could be
     // sabotaged by the website later in order to circumvent us.
@@ -432,14 +431,14 @@
   }, eventName);
 }
 
-function init(document)
+function init()
 {
   var shadow = null;
   var style = null;
   var observer = null;
   var tracer = null;
 
-  wrapWebSocket(document);
+  wrapWebSocket();
 
   function getPropertyFilters(callback)
   {
@@ -468,7 +467,7 @@
     // Stop the website from messing with our shadowRoot
     if ("shadowRoot" in Element.prototype)
     {
-      runInDocument(document, function()
+      runInDocument(function()
       {
         var ourShadowRoot = document.documentElement.shadowRoot;
         var desc = Object.getOwnPropertyDescriptor(Element.prototype, "shadowRoot");
@@ -560,7 +559,7 @@
       propertyFilters.apply();
 
       if (selectors.trace)
-        tracer = new ElementHidingTracer(document, selectors.selectors);
+        tracer = new ElementHidingTracer(selectors.selectors);
     };
 
     ext.backgroundPage.sendMessage({type: "get-selectors"}, function(response)
@@ -586,28 +585,8 @@
   document.addEventListener("load", function(event)
   {
     var element = event.target;
-
     if (/^i?frame$/.test(element.localName))
       checkCollapse(element);
-
-    if (/\bChrome\//.test(navigator.userAgent))
-    {
-      var contentDocument = getContentDocument(element);
-      if (contentDocument)
-      {
-        var contentWindow = contentDocument.defaultView;
-        if (contentDocument instanceof contentWindow.HTMLDocument)
-        {
-          // Prior to Chrome 37, content scripts cannot run in
-          // dynamically created frames. Also on Chrome 37-40
-          // document_start content scripts (like this one) don't
-          // run either in those frames due to https://crbug.com/416907.
-          // So we have to apply element hiding from the parent frame.
-          if (!("init" in contentWindow))
-            init(contentDocument);
-        }
-      }
-    }
   }, true);
 
   return updateStylesheet;
@@ -616,5 +595,5 @@
 if (document instanceof HTMLDocument)
 {
   checkSitekey();
-  window.updateStylesheet = init(document);
+  window.updateStylesheet = init();
 }