Add support for getting the sessionId from instrumentation and sending it to the client

pkg/analysis_server/lib/src/analysis_server.dart

Index: pkg/analysis_server/lib/src/analysis_server.dart
diff --git a/pkg/analysis_server/lib/src/analysis_server.dart b/pkg/analysis_server/lib/src/analysis_server.dart
index aa20e42dfc3d9b3e3f1a12847ee325ba8c49ebf8..d53d90b26d71a386e0b1b64ecb9b2f197f06e177 100644
--- a/pkg/analysis_server/lib/src/analysis_server.dart
+++ b/pkg/analysis_server/lib/src/analysis_server.dart
@@ -376,8 +376,9 @@ class AnalysisServer {
     _setupIndexInvalidation();
     pubSummaryManager =
         new PubSummaryManager(resourceProvider, '${io.pid}.temp');
-    Notification notification =
-        new ServerConnectedParams(VERSION, io.pid).toNotification();
+    Notification notification = new ServerConnectedParams(VERSION, io.pid,
+            sessionId: instrumentationService.sessionId)
+        .toNotification();
     channel.sendNotification(notification);
     channel.listen(handleRequest, onDone: done, onError: error);
     handlers = serverPlugin.createDomains(this);