dart2js: don't pass the supername to visitFields.

pkg/compiler/lib/src/js_emitter/old_emitter/class_emitter.dart

 // Copyright (c) 2013, 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.
 
 part of dart2js.js_emitter;
 
 class ClassEmitter extends CodeEmitterHelper {
 
   ClassStubGenerator get _stubGenerator =>
       new ClassStubGenerator(compiler, namer, backend);
@@ skipping 21 matching lines @@
       superName = namer.getNameOfClass(superclass);
     }
 
     if (classElement.isMixinApplication) {
       String mixinName = namer.getNameOfClass(computeMixinClass(classElement));
       superName = '$superName+$mixinName';
       emitter.needsMixinSupport = true;
     }
 
     ClassBuilder builder = new ClassBuilder(classElement, namer);
+    builder.superName = superName;
     emitClassConstructor(classElement, builder, onlyForRti: onlyForRti);
-    emitFields(classElement, builder, superName, onlyForRti: onlyForRti);
+    emitFields(classElement, builder, onlyForRti: onlyForRti);
     emitClassGettersSetters(classElement, builder, onlyForRti: onlyForRti);
     emitInstanceMembers(classElement, builder, onlyForRti: onlyForRti);
     emitter.typeTestEmitter.emitIsTests(classElement, builder);
     if (additionalProperties != null) {
       additionalProperties.forEach(builder.addProperty);
     }
 
     if (classElement == backend.closureClass) {
       // We add a special getter here to allow for tearing off a closure from
       // itself.
@@ skipping 30 matching lines @@
     String constructorName = namer.getNameOfClass(classElement);
     OutputUnit outputUnit =
         compiler.deferredLoadTask.outputUnitForElement(classElement);
     emitter.emitPrecompiledConstructor(
         outputUnit, constructorName, constructorAst);
   }
 
   /// Returns `true` if fields added.
   bool emitFields(Element element,
                   ClassBuilder builder,
-                  String superName,
                   { bool classIsNative: false,
                     bool emitStatics: false,
                     bool onlyForRti: false }) {
     assert(!emitStatics || !onlyForRti);
     if (element.isLibrary) {
       assert(invariant(element, emitStatics));
     } else if (!element.isClass) {
       throw new SpannableAssertionFailure(
           element, 'Must be a ClassElement or a LibraryElement');
     }
-    if (emitStatics) {
-      assert(invariant(element, superName == null, message: superName));
-    } else {
-      assert(invariant(element, superName != null));
-      builder.superName = superName;
-    }
     var fieldMetadata = [];
     bool hasMetadata = false;
     bool fieldsAdded = false;
 
     if (!onlyForRti) {
       visitFields(element, emitStatics,
                   (VariableElement field,
                    String name,
                    String accessorName,
                    bool needsGetter,
@@ skipping 183 matching lines @@
       bool hasSuper = superclass != null;
       if ((!typeVariableProperties.isEmpty && !hasSuper) ||
           (hasSuper && !equalElements(superclass.typeVariables, typeVars))) {
         classBuilder.addProperty('<>',
             new jsAst.ArrayInitializer.from(typeVariableProperties));
       }
     }
 
     List<jsAst.Property> statics = new List<jsAst.Property>();
     ClassBuilder staticsBuilder = new ClassBuilder(classElement, namer);
-    if (emitFields(classElement, staticsBuilder, null, emitStatics: true)) {
+    if (emitFields(classElement, staticsBuilder, emitStatics: true)) {
       jsAst.ObjectInitializer initializer =
         staticsBuilder.toObjectInitializer();
       compiler.dumpInfoTask.registerElementAst(classElement,
         initializer);
       jsAst.Node property = initializer.properties.single;
       compiler.dumpInfoTask.registerElementAst(classElement, property);
       statics.add(property);
     }
 
     ClassBuilder classProperties =
@@ skipping 275 matching lines @@
           js(r'this.$builtinTypeInfo && this.$builtinTypeInfo[#]', index);
     }
     jsAst.Expression convertRtiToRuntimeType =
         namer.elementAccess(backend.findHelper('convertRtiToRuntimeType'));
     compiler.dumpInfoTask.registerElementAst(element,
         builder.addProperty(name,
             js('function () { return #(#) }',
                 [convertRtiToRuntimeType, computeTypeVariable])));
   }
 }