Fix analyzer's treatment of mixin constructors.

pkg/analyzer/lib/src/generated/element_resolver.dart

 // Copyright (c) 2014, 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 engine.resolver.element_resolver;
 
 import 'dart:collection';
 
 import 'error.dart';
 import 'scanner.dart' as sc;
@@ skipping 1043 matching lines @@
       return null;
     }
     InterfaceType superType = enclosingClass.supertype;
     if (superType == null) {
       // TODO(brianwilkerson) Report this error.
       return null;
     }
     SimpleIdentifier name = node.constructorName;
     String superName = name != null ? name.name : null;
     ConstructorElement element = superType.lookUpConstructor(superName, _definingLibrary);
-    if (element == null) {
+    if (element == null ||
+        !enclosingClass.isSuperConstructorAccessible(element)) {
       if (name != null) {
         _resolver.reportErrorForNode(CompileTimeErrorCode.UNDEFINED_CONSTRUCTOR_IN_INITIALIZER, node, [superType.displayName, name]);
       } else {
         _resolver.reportErrorForNode(CompileTimeErrorCode.UNDEFINED_CONSTRUCTOR_IN_INITIALIZER_DEFAULT, node, [superType.displayName]);
       }
       return null;
     } else {
       if (element.isFactory) {
         _resolver.reportErrorForNode(CompileTimeErrorCode.NON_GENERATIVE_CONSTRUCTOR, node, [element]);
       }
@@ skipping 1570 matching lines @@
   @override
   Element get propagatedElement => null;
 
   @override
   Element get staticElement => null;
 
   @override
   void visitChildren(AstVisitor visitor) {
   }
 }