dart2js: Pass type information to constructor rather than add later.

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 a9a6d269587e3c20a2966513ef24bee606c4c302..62070c25bce81c36f03c140f24cb378714d47c72 100644
--- a/pkg/compiler/lib/src/js_emitter/model.dart
+++ b/pkg/compiler/lib/src/js_emitter/model.dart
@@ -229,6 +229,7 @@ class Class implements FieldContainer {
   /// noSuchMethod stubs in the special case that the class is Object.
   final List<StubMethod> noSuchMethodStubs;
   final List<Field> staticFieldsForReflection;
+  final bool hasRtiField; // Per-instance runtime type information pseudo-field.
   final bool onlyForRti;
   final bool isDirectlyInstantiated;
   final bool isNative;
@@ -262,7 +263,8 @@ class Class implements FieldContainer {
       this.checkedSetters,
       this.isChecks,
       this.functionTypeIndex,
-      {this.onlyForRti,
+      {this.hasRtiField,
+      this.onlyForRti,
       this.isDirectlyInstantiated,
       this.isNative}) {
     assert(onlyForRti != null);
@@ -297,7 +299,8 @@ class MixinApplication extends Class {
       List<StubMethod> checkedSetters,
       List<StubMethod> isChecks,
       js.Expression functionTypeIndex,
-      {bool onlyForRti,
+      {bool hasRtiField,
+      bool onlyForRti,
       bool isDirectlyInstantiated})
       : super(
             element,
@@ -312,6 +315,7 @@ class MixinApplication extends Class {
             checkedSetters,
             isChecks,
             functionTypeIndex,
+            hasRtiField: hasRtiField,
             onlyForRti: onlyForRti,
             isDirectlyInstantiated: isDirectlyInstantiated,
             isNative: false);