make completion managers responsible for their own caches

pkg/analysis_server/test/services/completion/imported_computer_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.services.completion.toplevel;
 
 import 'package:analysis_server/src/protocol.dart';
+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:analyzer/src/generated/engine.dart';
 import 'package:unittest/unittest.dart';
 
 import '../../reflective_tests.dart';
 import 'completion_test_util.dart';
 
 main() {
@@ skipping 30 matching lines @@
     context.applyChanges(changes);
     /*
      * Calculate a new completion at the same location
      */
     setUpComputer();
     request = new DartCompletionRequest(
         context,
         searchEngine,
         testSource,
         completionOffset,
-        cache);
+        cache,
+        new CompletionPerformance());
     expect(computeFast(), isTrue);
     expect(request.unit.element, isNull);
     List<CompletionSuggestion> newSuggestions = request.suggestions;
     if (newSuggestions.length == oldSuggestions.length) {
       if (!oldSuggestions.any(
           (CompletionSuggestion s) => !newSuggestions.contains(s))) {
         return;
       }
     }
     StringBuffer sb = new StringBuffer(
@@ skipping 67 matching lines @@
   test_Block_inherited_imported() {
     return super.test_Block_inherited_imported().then((_) {
       assertCached('E');
       assertCached('F');
       assertNotCached('e1');
       assertNotCached('i2');
       assertNotCached('m1');
     });
   }
 }