Another fix for unused elements.

pkg/analyzer/lib/src/generated/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;
 
 import "dart:math" as math;
 import 'dart:collection';
 
 import 'package:analyzer/src/generated/utilities_collection.dart';
@@ skipping 4513 matching lines @@
     }
     Element element = node.staticElement;
     bool isIdentifierRead = _isReadIdentifier(node);
     if (element is LocalVariableElement) {
       if (isIdentifierRead) {
         usedElements.addElement(element);
       }
     } else {
       _useIdentifierElement(node);
       if (element == null ||
-          element is! LocalElement && !identical(element, _enclosingExec)) {
+          element.enclosingElement is ClassElement &&
+              !identical(element, _enclosingExec)) {
         usedElements.members.add(node.name);
         if (isIdentifierRead) {
           usedElements.readMembers.add(node.name);
         }
       }
     }
   }
 
   /**
    * Marks an [Element] of [node] as used in the library.
@@ skipping 10865 matching lines @@
     nonFields.add(node);
     return null;
   }
 
   @override
   Object visitNode(AstNode node) => node.accept(TypeResolverVisitor_this);
 
   @override
   Object visitWithClause(WithClause node) => null;
 }