Add OCCURRENCES_CONTRIBUTOR_EXTENSION_POINT_ID.

pkg/analysis_server/lib/src/domain_analysis.dart

Index: pkg/analysis_server/lib/src/domain_analysis.dart
diff --git a/pkg/analysis_server/lib/src/domain_analysis.dart b/pkg/analysis_server/lib/src/domain_analysis.dart
index 8c6be5146b61c4ddec2c54e150fc93ad25a8a14d..48dcc67b630988a5737b596586108adba969a8ee 100644
--- a/pkg/analysis_server/lib/src/domain_analysis.dart
+++ b/pkg/analysis_server/lib/src/domain_analysis.dart
@@ -14,7 +14,10 @@ import 'package:analysis_server/src/constants.dart';
 import 'package:analysis_server/src/context_manager.dart';
 import 'package:analysis_server/src/domains/analysis/navigation.dart';
 import 'package:analysis_server/src/operation/operation_analysis.dart'
-    show NavigationOperation, sendAnalysisNotificationNavigation;
+    show
+        NavigationOperation,
+        OccurrencesOperation,
+        sendAnalysisNotificationNavigation;
 import 'package:analysis_server/src/protocol_server.dart';
 import 'package:analysis_server/src/services/dependencies/library_dependencies.dart';
 import 'package:analyzer/file_system/file_system.dart';
@@ -352,6 +355,9 @@ class AnalysisDomainImpl implements AnalysisDomain {
       if (service == AnalysisService.NAVIGATION) {
         server.scheduleOperation(new NavigationOperation(context, source));
       }
+      if (service == AnalysisService.OCCURRENCES) {
+        server.scheduleOperation(new OccurrencesOperation(context, source));
+      }
     }
   }