refactor and cleanup code completion

pkg/analysis_server/lib/src/domain_completion.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 domain.completion;
 
 import 'package:analysis_server/src/analysis_server.dart';
 import 'package:analysis_server/src/constants.dart';
 import 'package:analysis_server/src/protocol.dart';
-import 'package:analysis_services/completion/completion_computer.dart';
+import 'package:analysis_services/completion/completion_manager.dart';
 import 'package:analysis_services/completion/completion_suggestion.dart';
 import 'package:analysis_services/constants.dart';
 
 /**
  * Instances of the class [CompletionDomainHandler] implement a [RequestHandler]
  * that handles requests in the search domain.
  */
 class CompletionDomainHandler implements RequestHandler {
   /**
    * The analysis server that is using this handler to process requests.
@@ skipping 55 matching lines @@
       int replacementLength, Iterable<CompletionSuggestion> results, bool isLast) {
     Notification notification = new Notification(COMPLETION_RESULTS);
     notification.setParameter(ID, completionId);
     notification.setParameter(REPLACEMENT_OFFSET, replacementOffset);
     notification.setParameter(REPLACEMENT_LENGTH, replacementLength);
     notification.setParameter(RESULTS, results);
     notification.setParameter(LAST, isLast);
     server.sendNotification(notification);
   }
 }