fix mixins with factory constructors

pkg/dev_compiler/tool/input_sdk/private/ddc_runtime/classes.dart

 // Copyright (c) 2015, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 /// This library defines the operations that define and manipulate Dart
 /// classes.  Included in this are:
 ///   - Generics
 ///   - Class metadata
 ///   - Extension methods
 ///
@@ skipping 28 matching lines @@
   // Restore original Mixin JS constructor.
   Mixin.prototype.constructor = constructor;  
   // Dart constructors: run mixin constructors, then the base constructors.
   for (let memberName of $getOwnNamesAndSymbols($base)) {
     let member = $safeGetOwnProperty($base, memberName);
     if (typeof member == "function" && member.prototype === base.prototype) {
       $defineValue(Mixin, memberName, function(...args) {
         // Run mixin initializers. They cannot have arguments.
         // Run them backwards so most-derived mixin is initialized first.
         for (let i = $mixins.length - 1; i >= 0; i--) {
-          $mixins[i].new.call(this);
+          let m = $mixins[i];
+          (m[$mixinNew] || m.new).call(this);
         }
         // Run base initializer.
         $base[memberName].apply(this, args);
       }).prototype = Mixin.prototype;
     }
   }
 
   // Set the signature of the Mixin class to be the composition
   // of the signatures of the mixins.
   $setSignature(Mixin, {
@@ skipping 42 matching lines @@
 final _implements = JS('', 'Symbol("implements")');
 
 getImplements(clazz) => JS('', 'Object.hasOwnProperty.call(#, #) ? #[#] : null',
     clazz, _implements, clazz, _implements);
 
 /// The Symbol for storing type arguments on a specialized generic type.
 final _typeArguments = JS('', 'Symbol("typeArguments")');
 
 final _originalDeclaration = JS('', 'Symbol("originalDeclaration")');
 
+final mixinNew = JS('', 'Symbol("dart.mixinNew")');
+
 /// Wrap a generic class builder function with future flattening.
 flattenFutures(builder) => JS(
     '',
     '''(() => {
   function flatten(T) {
     if (!T) return $builder($dynamic);
     let futureClass = $getGenericClass($Future);
     //TODO(leafp): This only handles the direct flattening case.
     // It would probably be good to at least search up the class
     // hierarchy.  If we keep doing flattening long term, we may
@@ skipping 445 matching lines @@
 
 defineEnumValues(enumClass, names) {
   var values = [];
   for (var i = 0; i < JS('int', '#.length', names); i++) {
     var value = const_(JS('', 'new #.new(#)', enumClass, i));
     JS('', '#.push(#)', values, value);
     defineValue(enumClass, JS('', '#[#]', names, i), value);
   }
   JS('', '#.values = #', enumClass, constList(values, enumClass));
 }