Use elements/types in constants/values

pkg/compiler/lib/src/js_backend/constant_emitter.dart

 // Copyright (c) 2012, 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.
 
 import '../common.dart';
 import '../compiler.dart' show Compiler;
 import '../constants/values.dart';
 import '../elements/resolution_types.dart';
 import '../elements/elements.dart';
 import '../io/code_output.dart';
@@ skipping 259 matching lines @@
   @override
   jsAst.Expression visitType(TypeConstantValue constant, [_]) {
     ResolutionDartType type = constant.representedType;
     jsAst.Name typeName = namer.runtimeTypeName(type.element);
     return new jsAst.Call(getHelperProperty(backend.helpers.createRuntimeType),
         [js.quoteName(typeName)]);
   }
 
   @override
   jsAst.Expression visitInterceptor(InterceptorConstantValue constant, [_]) {
-    ClassElement interceptorClass = constant.dispatchedType.element;
+    ClassElement interceptorClass = constant.cls;
     return backend.emitter.interceptorPrototypeAccess(interceptorClass);
   }
 
   @override
   jsAst.Expression visitSynthetic(SyntheticConstantValue constant, [_]) {
     switch (constant.valueKind) {
       case SyntheticConstantKind.DUMMY_INTERCEPTOR:
       case SyntheticConstantKind.EMPTY_VALUE:
         return new jsAst.LiteralNumber('0');
       case SyntheticConstantKind.TYPEVARIABLE_REFERENCE:
@@ skipping 58 matching lines @@
       arguments.add(rtiEncoder.getTypeRepresentation(argument, unexpected));
     }
     return new jsAst.ArrayInitializer(arguments);
   }
 
   @override
   jsAst.Expression visitDeferred(DeferredConstantValue constant, [_]) {
     return constantReferenceGenerator(constant.referenced);
   }
 }