dart2js: native classes go through the normal code path.

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 5d36b36458299492ea9400ea9b3c2bbd133942f0..9a7ef02eca17fd0bc8c091b4f2f915de50c24f99 100644
--- a/pkg/compiler/lib/src/js_emitter/model.dart
+++ b/pkg/compiler/lib/src/js_emitter/model.dart
@@ -13,7 +13,6 @@ import '../common.dart';
 
 class Program {
   final List<Fragment> fragments;
-  final List<Class> nativeClasses;
   final bool outputContainsConstantList;
   final bool outputContainsNativeClasses;
   /// A map from load id to the list of fragments that need to be loaded.
@@ -23,7 +22,6 @@ class Program {
   final Map<Class, Map<String, js.Expression>> additionalProperties;
 
   Program(this.fragments,
-          this.nativeClasses,
           this.additionalProperties,
           this.loadMap,
           {this.outputContainsNativeClasses,