Add node modules and compiled JavaScript from main

node_modules/jsdom/lib/jsdom/living/cssom/StyleSheetList-impl.js

@@ -0,0 +1,38 @@
+"use strict";
+
+const idlUtils = require("../generated/utils.js");
+
+exports.implementation = class StyleSheetList {
+  constructor() {
+    this._list = [];
+  }
+
+  get length() {
+    return this._list.length;
+  }
+
+  item(index) {
+    const result = this._list[index];
+    return result !== undefined ? result : null;
+  }
+
+  get [idlUtils.supportedPropertyIndices]() {
+    return this._list.keys();
+  }
+
+  _add(sheet) {
+    const { _list } = this;
+    if (!_list.includes(sheet)) {
+      _list.push(sheet);
+    }
+  }
+
+  _remove(sheet) {
+    const { _list } = this;
+
+    const index = _list.indexOf(sheet);
+    if (index >= 0) {
+      _list.splice(index, 1);
+    }
+  }
+};