Added tests; improved test output; code clean-up

pkg/analyzer/lib/src/generated/error.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 analyzer.src.generated.error;
 
 import 'dart:collection';
 
 import 'package:analyzer/dart/ast/ast.dart' show AstNode;
 import 'package:analyzer/dart/ast/token.dart';
@@ skipping 3042 matching lines @@
 
   /**
    * The type of the error.
    */
   ErrorType get type;
 
   /**
    * The unique name of this error code.
    */
   String get uniqueName => "$runtimeType.$name";
+
+  @override
+  String toString() => uniqueName;
 }
 
 /**
  * The properties that can be associated with an [AnalysisError].
  */
 class ErrorProperty extends Enum<ErrorProperty> {
   /**
    * A property whose value is a list of [FieldElement]s that are final, but
    * not initialized by a constructor.
    */
@@ skipping 2671 matching lines @@
    * Initialize a newly created error code to have the given [name].
    */
   const TodoCode(String name) : super(name, "{0}");
 
   @override
   ErrorSeverity get errorSeverity => ErrorSeverity.INFO;
 
   @override
   ErrorType get type => ErrorType.TODO;
 }