Issue 2879 - Move element selection into the content process

lib/child/nodeInfo.js

Index: lib/child/nodeInfo.js
===================================================================
--- a/lib/child/nodeInfo.js
+++ b/lib/child/nodeInfo.js
@@ -3,38 +3,20 @@
  * version 2.0 (the "License"). You can obtain a copy of the License at
  * http://mozilla.org/MPL/2.0/.
  */
 
 "use strict";
 
 let {Services} = Cu.import("resource://gre/modules/Services.jsm", {});
 
-let messageManager = require("messageManager");
-
 let processID = Services.appinfo.processID;
 let maxNodeID = 0;
 let nodes = new Map();
 
-messageManager.addMessageListener("ElemHideHelper:GetNodeInfo", onGetNodeInfo);
-onShutdown.add(() =>
-{
-  messageManager.removeMessageListener("ElemHideHelper:GetNodeInfo", onGetNodeInfo);
-});
-
-function onGetNodeInfo(message)
-{
-  if (Cu.isCrossProcessWrapper(message.objects.element))
-    return;
-
-  let nodeInfo = getNodeInfo(message.objects.element);
-  nodeInfo.messageId = message.data;
-  messageManager.sendAsyncMessage("ElemHideHelper:GetNodeInfo:Response", nodeInfo);
-}
-
 function getNodeInfo(node)
 {
   let nodeData = getNodeData(node);
   if (nodeData)
   {
     let nodeID = processID + "-" + (++maxNodeID);
     nodes.set(nodeID, {document: node.ownerDocument, style: null});
     return {