Report HintCode.UNUSED_ELEMENT for classes.

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 engine.error;
 
 import 'dart:collection';
 import 'java_core.dart';
 import 'source.dart';
 import 'scanner.dart' show Token;
@@ skipping 2603 matching lines @@
    * Unnecessary type checks, the result is always true.
    */
   static const HintCode UNNECESSARY_TYPE_CHECK_FALSE = const HintCode('UNNECESSARY_TYPE_CHECK_FALSE', "Unnecessary type check, the result is always false");
 
   /**
    * Unnecessary type checks, the result is always false.
    */
   static const HintCode UNNECESSARY_TYPE_CHECK_TRUE = const HintCode('UNNECESSARY_TYPE_CHECK_TRUE', "Unnecessary type check, the result is always true");
 
   /**
+   * See [Modifier.IS_USED_IN_LIBRARY].
+   */
+  static const HintCode UNUSED_ELEMENT = const HintCode('UNUSED_ELEMENT', "The {0} '{1}' is not used");
+
+  /**
    * Unused imports are imports which are never used.
    */
   static const HintCode UNUSED_IMPORT = const HintCode('UNUSED_IMPORT', "Unused import");
 
   /**
    * Unused local variables are local varaibles which are never read.
    */
   static const HintCode UNUSED_LOCAL_VARIABLE = const HintCode('UNUSED_LOCAL_VARIABLE', "The value of the local variable '{0}' is not used");
 
   /**
@@ skipping 1434 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;
 }