Add a message for analysis server to indicate a successful connection.

pkg/analysis_server/lib/src/socket_server.dart

Index: pkg/analysis_server/lib/src/socket_server.dart
diff --git a/pkg/analysis_server/lib/src/socket_server.dart b/pkg/analysis_server/lib/src/socket_server.dart
index 3d5949f12ae5994907a350e3e93d3be7ca8b2296..1d74d62a5e583f7ea818731ad96e28ea782b1f40 100644
--- a/pkg/analysis_server/lib/src/socket_server.dart
+++ b/pkg/analysis_server/lib/src/socket_server.dart
@@ -29,8 +29,6 @@ class SocketServer {
    */
   void createAnalysisServer(ServerCommunicationChannel serverChannel) {
     if (analysisServer != null) {
-      // TODO(paulberry): add a message to the protocol so that the server can
-      // inform the client of a successful connection.
       var error = new RequestError.serverAlreadyStarted();
       serverChannel.sendResponse(new Response('', error));
       serverChannel.listen((Request request) {