Remove copies of ExportNamespaceBuilder and PublicNamespaceBuilder.

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 analyzer.src.generated.resolver;
 
 import 'dart:collection';
 
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/ast/token.dart';
@@ skipping 6562 matching lines @@
    * Create a mapping table representing the export namespace of the given library.
    *
    * @param library the library whose public namespace is to be created
    * @param visitedElements a set of libraries that do not need to be visited when processing the
    *          export directives of the given library because all of the names defined by them will
    *          be added by another library
    * @return the mapping table that was created
    */
   HashMap<String, Element> _createExportMapping(
       LibraryElement library, HashSet<LibraryElement> visitedElements) {
-    // Check if the export namespace has been already computed.
-    {
-      Namespace exportNamespace = library.exportNamespace;
-      if (exportNamespace != null) {
-        return exportNamespace.definedNames;
-      }
-    }
-    // TODO(scheglov) Remove this after switching to the new task model.
     visitedElements.add(library);
     try {
       HashMap<String, Element> definedNames = new HashMap<String, Element>();
       for (ExportElement element in library.exports) {
         LibraryElement exportedLibrary = element.exportedLibrary;
         if (exportedLibrary != null &&
             !visitedElements.contains(exportedLibrary)) {
           //
           // The exported library will be null if the URI does not reference a
           // valid library.
@@ skipping 6190 matching lines @@
     nonFields.add(node);
     return null;
   }
 
   @override
   Object visitNode(AstNode node) => node.accept(TypeResolverVisitor_this);
 
   @override
   Object visitWithClause(WithClause node) => null;
 }