Clean up hints after a new hint was introduced

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/src/context/cache.dart' show CacheEntry;
 import 'package:analyzer/src/context/context.dart';
 import 'package:analyzer/src/dart/element/element.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/source.dart'
-    show DartUriResolver, Source, SourceFactory, SourceKind;
+    show Source, SourceFactory, SourceKind;
 import 'package:analyzer/src/summary/idl.dart';
 import 'package:analyzer/src/summary/resynthesize.dart';
 import 'package:analyzer/src/task/dart.dart';
 import 'package:analyzer/task/dart.dart';
 import 'package:analyzer/task/model.dart'
     show AnalysisTarget, ResultDescriptor, TargetedResult;
 
 class SdkSummaryResultProvider implements SummaryResultProvider {
   final InternalAnalysisContext context;
   final PackageBundle bundle;
@@ skipping 391 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;
   }
 }