Fixes.

node_modules/parse5/lib/utils/mixin.js

@@ -0,0 +1,18 @@
+'use strict';
+
+var Mixin = module.exports = function (host) {
+    var originalMethods = {},
+        overriddenMethods = this._getOverriddenMethods(this, originalMethods);
+
+    Object.keys(overriddenMethods).forEach(function (key) {
+        if (typeof overriddenMethods[key] === 'function') {
+            originalMethods[key] = host[key];
+            host[key] = overriddenMethods[key];
+        }
+    });
+};
+
+Mixin.prototype._getOverriddenMethods = function () {
+    throw new Error('Not implemented');
+};
+