rename completion source files to match content

pkg/analysis_server/test/services/completion/keyword_contributor_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.dart.keyword;
 
 import 'package:analysis_server/src/protocol.dart';
 import 'package:analysis_server/src/services/completion/dart_completion_manager.dart';
-import 'package:analysis_server/src/services/completion/keyword_computer.dart';
+import 'package:analysis_server/src/services/completion/keyword_contributor.dart';
 import 'package:analyzer/src/generated/scanner.dart';
 import 'package:unittest/unittest.dart';
 
 import '../../reflective_tests.dart';
 import 'completion_test_util.dart';
 
 main() {
   groupSep = ' | ';
   runReflectiveTests(KeywordContributorTest);
 }
@@ skipping 436 matching lines @@
     sorted.forEach((k) => msg.writeln('  Keyword.${k.name},'));
   }
 
   bool _equalSets(Iterable<Keyword> iter1, Iterable<Keyword> iter2) {
     if (iter1.length != iter2.length) return false;
     if (iter1.any((k) => !iter2.contains(k))) return false;
     if (iter2.any((k) => !iter1.contains(k))) return false;
     return true;
   }
 }