Add ImportElement and ExportElement

pkg/compiler/lib/src/elements/names.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.
 
 part of elements;
 
 /// A [Name] represents the abstraction of a Dart identifier which takes privacy
 /// and setter into account.
 // TODO(johnniwinther): Try to share logic with [Selector].
 abstract class Name {
@@ skipping 92 matching lines @@
 
   bool get isPrivate => true;
 
   int get hashCode => super.hashCode + 13 * library.hashCode;
 
   bool operator ==(other) {
     if (other is! PrivateName) return false;
     return super==(other) && library == other.library;
   }
 
-  String toString() => '${library.getLibraryName()}#${super.toString()}';
+  String toString() => '${library.libraryName}#${super.toString()}';
 }