Use the NavigationCollector from analyzer_plugin to avoid duplication

pkg/analysis_server/lib/src/computer/new_notifications.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.
 
 import 'package:analysis_server/protocol/protocol_generated.dart' as protocol;
 import 'package:analysis_server/src/analysis_server.dart' show AnalysisServer;
-import 'package:analysis_server/src/domains/analysis/navigation.dart';
 import 'package:analysis_server/src/domains/analysis/navigation_dart.dart';
 import 'package:analysis_server/src/domains/analysis/occurrences.dart';
 import 'package:analysis_server/src/domains/analysis/occurrences_dart.dart';
 import 'package:analysis_server/src/protocol_server.dart' as protocol;
 import 'package:analyzer/src/dart/analysis/driver.dart';
+import 'package:analyzer_plugin/src/utilities/navigation/navigation.dart';
 
 void new_sendDartNotificationNavigation(
     AnalysisServer analysisServer, AnalysisResult result) {
   var unit = result.unit;
   if (unit != null) {
     NavigationCollectorImpl collector = new NavigationCollectorImpl();
     computeDartNavigation(collector, unit, null, null);
     collector.createRegions();
     var params = new protocol.AnalysisNavigationParams(
         result.path, collector.regions, collector.targets, collector.files);
@@ skipping 13 matching lines @@
   }
 }
 
 void new_sendErrorNotification(
     AnalysisServer analysisServer, AnalysisResult result) {
   var serverErrors = protocol.doAnalysisError_listFromEngine(
       result.driver.analysisOptions, result.lineInfo, result.errors);
   var params = new protocol.AnalysisErrorsParams(result.path, serverErrors);
   analysisServer.sendNotification(params.toNotification());
 }