refactor ContributionSorter to use new API

pkg/analysis_server/test/domain_completion_test.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 test.domain.completion;
 
 import 'dart:async';
 
 import 'package:analysis_server/completion/completion_core.dart'
     show CompletionRequest, CompletionResult;
+import 'package:analysis_server/completion/completion_dart.dart' as newApi;
 import 'package:analysis_server/src/analysis_server.dart';
 import 'package:analysis_server/src/channel/channel.dart';
 import 'package:analysis_server/src/constants.dart';
 import 'package:analysis_server/src/context_manager.dart';
 import 'package:analysis_server/src/domain_analysis.dart';
 import 'package:analysis_server/src/domain_completion.dart';
 import 'package:analysis_server/src/plugin/server_plugin.dart';
 import 'package:analysis_server/src/protocol.dart';
 import 'package:analysis_server/src/services/completion/completion_manager.dart';
 import 'package:analysis_server/src/services/completion/contribution_sorter.dart';
@@ skipping 453 matching lines @@
   test_invocation_sdk_relevancy_off() {
     var originalSorter = DartCompletionManager.defaultContributionSorter;
     var mockSorter = new MockRelevancySorter();
     DartCompletionManager.defaultContributionSorter = mockSorter;
     addTestFile('main() {Map m; m.^}');
     return getSuggestions().then((_) {
       // Assert that the CommonUsageComputer has been replaced
       expect(suggestions.any((s) => s.relevance == DART_RELEVANCE_COMMON_USAGE),
           isFalse);
       DartCompletionManager.defaultContributionSorter = originalSorter;
-      expect(mockSorter.count, 2);
+      mockSorter.enabled = false;
     });
   }
 
   test_invocation_sdk_relevancy_on() {
     addTestFile('main() {Map m; m.^}');
     return getSuggestions().then((_) {
       // Assert that the CommonUsageComputer is working
       expect(suggestions.any((s) => s.relevance == DART_RELEVANCE_COMMON_USAGE),
           isTrue);
     });
@@ skipping 213 matching lines @@
 
   @override
   TimestampedData<String> getContents(Source source) {
     return source.contents;
   }
 
   noSuchMethod(Invocation invocation) => super.noSuchMethod(invocation);
 }
 
 class MockRelevancySorter implements ContributionSorter {
-  int count = 0;
+  bool enabled = true;
 
   @override
-  void sort(DartCompletionRequest request) {
-    if (++count > 2) {
+  void sort(newApi.DartCompletionRequest request,
+      List<CompletionSuggestion> suggestions) {
+    if (!enabled) {
       throw 'unexpected sort';
     }
   }
 }
 
 /**
  * Mock stream for tracking calls to listen and subscription.cancel.
  */
 class MockStream<E> implements Stream<E> {
   MockSubscription<E> mockSubscription = new MockSubscription<E>();
@@ skipping 103 matching lines @@
 }
     ''');
     await waitForTasksFinished();
     Request request =
         new CompletionGetSuggestionsParams(testFile, 0).toRequest('0');
     Response response = handler.handleRequest(request);
     expect(response.error, isNotNull);
     expect(response.error.code, RequestErrorCode.NO_INDEX_GENERATED);
   }
 }