Compute the correct signature for default constructors.

dart/sdk/lib/_internal/compiler/implementation/elements/modelx.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.
 
 library elements.modelx;
 
 import 'dart:collection' show LinkedHashMap;
 
 import 'elements.dart';
 import '../../compiler.dart' as api;
@@ skipping 1380 matching lines @@
 
 /**
  * A constructor that is not defined in the source code but rather implied by
  * the language semantics.
  *
  * This class is used to represent default constructors and forwarding
  * constructors for mixin applications.
  */
 class SynthesizedConstructorElementX extends FunctionElementX {
   final FunctionElement superMember;
+  final bool isDefaultConstructor;
 
   SynthesizedConstructorElementX(SourceString name,
                                  this.superMember,
-                                 Element enclosing)
+                                 Element enclosing,
+                                 this.isDefaultConstructor)

[ngeoffray, 2013/08/08 21:55:24]

Did you consider a named parameter?

       : super(name,
               ElementKind.GENERATIVE_CONSTRUCTOR,
               Modifiers.EMPTY,
               enclosing);
 
   SynthesizedConstructorElementX.forDefault(superMember, Element enclosing)
-      : this(const SourceString(''), superMember, enclosing);
+      : this(const SourceString(''), superMember, enclosing, true);
 
   Token position() => enclosingElement.position();
 
   bool get isSynthesized => true;
 
   FunctionElement get targetConstructor => superMember;
 
   FunctionSignature computeSignature(compiler) {
+    if (isDefaultConstructor) {
+      return new FunctionSignatureX(
+          const Link<Element>(), const Link<Element>(), 0, 0, false,
+          getEnclosingClass().thisType);
+    }
     if (superMember.isErroneous()) {
       return compiler.objectClass.localLookup(
           const SourceString('')).computeSignature(compiler);
     }
     return superMember.computeSignature(compiler);
   }
 
   get declaration => this;
   get implementation => this;
   get defaultImplementation => this;
@@ skipping 749 matching lines @@
 
   MetadataAnnotation ensureResolved(Compiler compiler) {
     if (resolutionState == STATE_NOT_STARTED) {
       compiler.resolver.resolveMetadataAnnotation(this);
     }
     return this;
   }
 
   String toString() => 'MetadataAnnotation($value, $resolutionState)';
 }