Navigation computer and two variants of tests for it.

pkg/analysis_server/lib/src/operation/operation_analysis.dart

Index: pkg/analysis_server/lib/src/operation/operation_analysis.dart
diff --git a/pkg/analysis_server/lib/src/operation/operation_analysis.dart b/pkg/analysis_server/lib/src/operation/operation_analysis.dart
index ceac59de6167675b5e4a24c2f712df5ee646b64e..ed8cfd87d6879e58606c2799f4b7ae5c48b5e53a 100644
--- a/pkg/analysis_server/lib/src/operation/operation_analysis.dart
+++ b/pkg/analysis_server/lib/src/operation/operation_analysis.dart
@@ -72,6 +72,9 @@ class PerformAnalysisOperation extends ServerOperation {
         if (server.hasAnalysisSubscription(AnalysisService.HIGHLIGHTS, file)) {
           sendAnalysisNotificationHighlights(server, file, dartUnit);
         }
+        if (server.hasAnalysisSubscription(AnalysisService.NAVIGATION, file)) {
+          sendAnalysisNotificationNavigation(server, file, dartUnit);
+        }
       }
       if (!source.isInSystemLibrary) {
         sendAnalysisNotificationErrors(server, file, notice.errors);
@@ -98,6 +101,16 @@ void sendAnalysisNotificationHighlights(AnalysisServer server,
   server.sendNotification(notification);
 }
 
+void sendAnalysisNotificationNavigation(AnalysisServer server,
+                                        String file, CompilationUnit dartUnit) {
+  Notification notification = new Notification(NOTIFICATION_NAVIGATION);
+  notification.setParameter(FILE, file);
+  notification.setParameter(
+      REGIONS,
+      new DartUnitNavigationComputer(dartUnit).compute());
+  server.sendNotification(notification);
+}
+
 Map<String, Object> errorToJson(AnalysisError analysisError) {
   // TODO(paulberry): move this function into the AnalysisError class.
   ErrorCode errorCode = analysisError.errorCode;