Issue 3968. Report error if cycle in redirecting factory constructors

compiler/java/com/google/dart/compiler/resolver/ConstructorElementImplementation.java

 // 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.
 
 package com.google.dart.compiler.resolver;
 
 import com.google.dart.compiler.ast.DartIdentifier;
 import com.google.dart.compiler.ast.DartMethodDefinition;
 import com.google.dart.compiler.ast.DartNode;
 import com.google.dart.compiler.ast.DartParameterizedTypeNode;
 import com.google.dart.compiler.ast.DartPropertyAccess;
 
 class ConstructorElementImplementation extends MethodElementImplementation
     implements ConstructorNodeElement {
   private final ClassElement constructorType;
   private final String rawName;
   private ConstructorElement defaultConstructor;
+  private ConstructorElement redirectingFactoryConstructor;
 
   private ConstructorElementImplementation(DartMethodDefinition node,
                              String name,
                              ClassElement declaringClass,
                              ClassElement constructorType) {
     super(node, name, declaringClass);
     this.constructorType = constructorType;
     this.rawName = getRawName(node.getName());
   }
 
@@ skipping 40 matching lines @@
   @Override
   public ConstructorElement getDefaultConstructor() {
     return defaultConstructor;
   }
 
   @Override
   public void setDefaultConstructor(ConstructorElement defaultConstructor) {
     this.defaultConstructor = defaultConstructor;
   }
 
+  @Override
+  public ConstructorElement getRedirectingFactoryConstructor() {
+    return redirectingFactoryConstructor;
+  }
+  
+  public void setRedirectingFactoryConstructor(ConstructorElement redirectingFactoryConstructor) {
+    this.redirectingFactoryConstructor = redirectingFactoryConstructor;
+  }
+
   public static ConstructorElementImplementation fromMethodNode(DartMethodDefinition node,
                                                   String name,
                                                   ClassElement declaringClass,
                                                   ClassElement constructorType) {
     return new ConstructorElementImplementation(node, name, declaringClass, constructorType);
   }
 }