avoid infinite loop when trying to load a broken module

node_modules/ace/lib/ace/worker/worker.js

@@ -1,8 +1,9 @@
 "no use strict";
 ;(function(window) {
-if (typeof window.window != "undefined" && window.document) {
+if (typeof window.window != "undefined" && window.document)
+    return;
+if (window.require && window.define)
     return;
-}
 
 window.console = function() {
     var msgs = Array.prototype.slice.call(arguments, 0);
@@ -73,6 +74,7 @@ window.require = function(parentId, id) {
     var path = chunks.join("/") + ".js";
     
     window.require.id = id;
+    window.require.modules[id] = {}; // prevent infinite loop on broken modules
     importScripts(path);
     return window.require(parentId, id);
 };