dart2js: use model in native emitter.

pkg/compiler/lib/src/js_emitter/model.dart

Index: pkg/compiler/lib/src/js_emitter/model.dart
diff --git a/pkg/compiler/lib/src/js_emitter/model.dart b/pkg/compiler/lib/src/js_emitter/model.dart
index b1e20c10bdb660dc213a6adf7b1c3c8896c974f6..f4e7ef541d6c76041eb0f26e6ec92459a00cde5a 100644
--- a/pkg/compiler/lib/src/js_emitter/model.dart
+++ b/pkg/compiler/lib/src/js_emitter/model.dart
@@ -13,11 +13,15 @@ import '../common.dart';
 
 class Program {
   final List<Fragment> fragments;
+  final List<Class> nativeClasses;
   final bool outputContainsConstantList;
   /// A map from load id to the list of fragments that need to be loaded.
   final Map<String, List<Fragment>> loadMap;
 
-  Program(this.fragments, this.outputContainsConstantList, this.loadMap);
+  Program(this.fragments,
+          this.nativeClasses,
+          this.outputContainsConstantList,
+          this.loadMap);
 
   bool get isSplit => fragments.length > 1;
   Iterable<Fragment> get deferredFragments => fragments.skip(1);
@@ -168,6 +172,7 @@ class Class {
   final List<InstanceField> fields;
   final bool onlyForRti;
   final bool isDirectlyInstantiated;
+  final bool isNative;
 
   /// Whether the class must be evaluated eagerly.
   bool isEager = false;
@@ -175,9 +180,11 @@ class Class {
   Class(this.element,
         this.name, this.holder, this.methods, this.fields,
         {this.onlyForRti,
-         this.isDirectlyInstantiated}) {
+         this.isDirectlyInstantiated,
+         this.isNative}) {
     assert(onlyForRti != null);
     assert(isDirectlyInstantiated != null);
+    assert(isNative != null);
   }
 
   bool get isMixinApplication => false;
@@ -205,7 +212,8 @@ class MixinApplication extends Class {
       : super(element,
               name, holder, methods, fields,
               onlyForRti: onlyForRti,
-              isDirectlyInstantiated: isDirectlyInstantiated);
+              isDirectlyInstantiated: isDirectlyInstantiated,
+              isNative: false);

[sra1, 2015/01/21 06:27:06]

I believe that you can create a custom element that is simply a mixin
application.

 
   bool get isMixinApplication => true;
   Class get mixinClass => _mixinClass;