Get the most basic mixin applications working.

sdk/lib/_internal/compiler/implementation/elements/elements.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.
 
 library elements;
 
 import 'dart:uri';
 
 import 'modelx.dart';
 import '../tree/tree.dart';
@@ skipping 621 matching lines @@
 
   ClassElement get patch;
   ClassElement get origin;
   ClassElement get declaration;
   ClassElement get implementation;
 
   int get supertypeLoadState;
   int get resolutionState;
   SourceString get nativeTagInfo;
 
+  bool get isMixinApplication;
   bool get hasBackendMembers;
   bool get hasLocalScopeMembers;
 
   // TODO(kasperl): These are bit fishy. Do we really need them?
   void set rawType(InterfaceType value);
   void set thisType(InterfaceType value);
   void set supertype(DartType value);
   void set allSupertypes(Link<DartType> value);
   void set interfaces(Link<DartType> value);
   void set patch(ClassElement value);
@@ skipping 11 matching lines @@
   bool isSubclassOf(ClassElement cls);
   bool implementsInterface(ClassElement intrface);
   bool isShadowedByField(Element fieldMember);
 
   ClassNode parseNode(Compiler compiler);
   ClassElement ensureResolved(Compiler compiler);
 
   void addMember(Element element, DiagnosticListener listener);
   void addToScope(Element element, DiagnosticListener listener);
 
+  /**
+   * Add a synthetic nullary constructor if there are no other
+   * constructors.
+   */
+  void addDefaultConstructorIfNeeded(Compiler compiler);
+
   void addBackendMember(Element element);
   void reverseBackendMembers();
 
   Element lookupMember(SourceString memberName);
   Element lookupSelector(Selector selector);
 
   Element lookupLocalMember(SourceString memberName);
   Element lookupBackendMember(SourceString memberName);
   Element lookupSuperMember(SourceString memberName);
 
@@ skipping 67 matching lines @@
   Element get annotatedElement;
   int get resolutionState;
   Token get beginToken;
 
   // TODO(kasperl): Try to get rid of these.
   void set annotatedElement(Element value);
   void set resolutionState(int value);
 
   MetadataAnnotation ensureResolved(Compiler compiler);
 }