Add DartSdk.getLinkedBundle() and use it in PubSummaryManager.

pkg/analyzer/lib/src/summary/summary_sdk.dart

 // Copyright (c) 2015, 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.summary.summary_sdk;
 
 import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/dart/element/type.dart';
+import 'package:analyzer/file_system/file_system.dart' show ResourceProvider;
 import 'package:analyzer/src/context/cache.dart' show CacheEntry;
 import 'package:analyzer/src/context/context.dart';
 import 'package:analyzer/src/dart/element/type.dart';
 import 'package:analyzer/src/generated/constant.dart';
 import 'package:analyzer/src/generated/engine.dart';
 import 'package:analyzer/src/generated/resolver.dart';
 import 'package:analyzer/src/generated/sdk.dart';
 import 'package:analyzer/src/generated/source.dart'
     show DartUriResolver, Source, SourceFactory;
 import 'package:analyzer/src/summary/idl.dart';
 import 'package:analyzer/src/summary/package_bundle_reader.dart';
 import 'package:analyzer/src/summary/resynthesize.dart';
 import 'package:analyzer/src/task/dart.dart';
 import 'package:analyzer/task/model.dart' show ResultDescriptor, TargetedResult;
-import 'package:analyzer/file_system/file_system.dart' show ResourceProvider;
 
 class SdkSummaryResultProvider extends ResynthesizerResultProvider {
   final SummaryTypeProvider typeProvider = new SummaryTypeProvider();
 
   SdkSummaryResultProvider(
       InternalAnalysisContext context, PackageBundle bundle, bool strongMode)
       : super(context, new SummaryDataStore(const <String>[])) {
     addBundle(null, bundle);
     createResynthesizer(null, typeProvider);
     _buildCoreLibrary();
@@ skipping 128 matching lines @@
   List<String> get uris {
     throw new UnimplementedError();
   }
 
   @override
   Source fromFileUri(Uri uri) {
     return null;
   }
 
   @override
+  PackageBundle getLinkedBundle() => _bundle;
+
+  @override
   SdkLibrary getSdkLibrary(String uri) {
     // This is not quite correct, but currently it's used only in
     // to report errors on importing or exporting of internal libraries.
     return null;
   }
 
   @override
   Source mapDartUri(String uriStr) {
     Uri uri = Uri.parse(uriStr);
     return _uriResolver.resolveAbsolute(uri);
@@ skipping 228 matching lines @@
    * throw a [StateError] if there is no class with the given name.
    */
   InterfaceType _getType(LibraryElement library, String name) {
     Element element = library.getType(name);
     if (element == null) {
       throw new StateError("No definition of type $name");
     }
     return (element as ClassElement).type;
   }
 }