make completion managers responsible for their own caches

pkg/analysis_server/test/services/completion/completion_test_util.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.services.completion.util;
 
 import 'dart:async';
 
 import 'package:analysis_server/src/protocol.dart' as protocol show Element,
     ElementKind;
 import 'package:analysis_server/src/protocol.dart' hide Element, ElementKind;
+import 'package:analysis_server/src/services/completion/completion_manager.dart';
 import 'package:analysis_server/src/services/completion/dart_completion_cache.dart';
 import 'package:analysis_server/src/services/completion/dart_completion_manager.dart';
 import 'package:analysis_server/src/services/completion/imported_computer.dart';
 import 'package:analysis_server/src/services/completion/invocation_computer.dart';
 import 'package:analysis_server/src/services/completion/local_computer.dart';
 import 'package:analysis_server/src/services/index/index.dart';
 import 'package:analysis_server/src/services/index/local_memory_index.dart';
 import 'package:analysis_server/src/services/search/search_engine_internal.dart';
 import 'package:analyzer/src/generated/ast.dart';
 import 'package:analyzer/src/generated/element.dart';
@@ skipping 36 matching lines @@
     expect(nextOffset, equals(-1), reason: 'too many ^');
     content = content.substring(0, completionOffset) +
         content.substring(completionOffset + 1);
     testSource = addSource(testFile, content);
     cache = new DartCompletionCache(context, testSource);
     request = new DartCompletionRequest(
         context,
         searchEngine,
         testSource,
         completionOffset,
-        cache);
+        cache,
+        new CompletionPerformance());
   }
 
   void assertNoSuggestions({CompletionSuggestionKind kind: null}) {
     if (kind == null) {
       if (request.suggestions.length > 0) {
         failedCompletion('Expected no suggestions', request.suggestions);
       }
       return;
     }
     CompletionSuggestion suggestion = request.suggestions.firstWhere(
@@ skipping 1976 matching lines @@
       assertNotSuggested('bar2');
       assertNotSuggested('_B');
       assertSuggestLocalClass('Y');
       assertSuggestLocalClass('C');
       assertSuggestLocalVariable('f', null);
       assertNotSuggested('x');
       assertNotSuggested('e');
     });
   }
 }