Element model cleanup + prepare for easier reimplementation.

pkg/compiler/lib/src/resolution/constructors.dart

 // Copyright (c) 2015, 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 resolution;
 
 class InitializerResolver {
   final ResolverVisitor visitor;
   final Map<Element, Node> initialized;
   Link<Node> initializers;
@@ skipping 123 matching lines @@
     return calledConstructor;
   }
 
   void resolveImplicitSuperConstructorSend(FunctionElement constructor,
                                            FunctionExpression functionNode) {
     // If the class has a super resolve the implicit super call.
     ClassElement classElement = constructor.enclosingClass;
     ClassElement superClass = classElement.superclass;
     if (classElement != visitor.compiler.objectClass) {
       assert(superClass != null);
-      assert(superClass.resolutionState == STATE_DONE);
+      assert(superClass.isResolved);
 
       final bool isSuperCall = true;
       ClassElement lookupTarget = getSuperOrThisLookupTarget(constructor,
                                                              isSuperCall,
                                                              functionNode);
       Selector constructorSelector = new Selector.callDefaultConstructor();
       Element calledConstructor = lookupTarget.lookupConstructor(
           constructorSelector.name);
 
       final String className = lookupTarget.name;
@@ skipping 314 matching lines @@
     return element;
   }
 
   /// Assumed to be called by [resolveRedirectingFactory].
   Element visitRedirectingFactoryBody(RedirectingFactoryBody node) {
     Node constructorReference = node.constructorReference;
     return finishConstructorReference(visit(constructorReference),
         constructorReference, node);
   }
 }