update client to use channel rather than socket

pkg/analysis_server/lib/src/channel.dart

Index: pkg/analysis_server/lib/src/channel.dart
diff --git a/pkg/analysis_server/lib/src/channel.dart b/pkg/analysis_server/lib/src/channel.dart
index 103c2b77acc39d9420ab98f31e89ac446fc8c9a2..9382eba7cf100e5bf43f2ed414f7b63232245ad8 100644
--- a/pkg/analysis_server/lib/src/channel.dart
+++ b/pkg/analysis_server/lib/src/channel.dart
@@ -29,6 +29,11 @@ abstract class CommunicationChannel {
   void sendNotification(Notification notification);
 
   /**
+   * Send the given [request] to the server.
+   */
+  void sendRequest(Request request);
+
+  /**
    * Send the given [response] to the client.
    */
   void sendResponse(Response response);
@@ -62,6 +67,12 @@ class WebSocketChannel implements CommunicationChannel {
   }
 
   @override
+  void sendRequest(Request request) {
+    JsonEncoder encoder = const JsonEncoder(null);

[Brian Wilkerson, 2014/02/26 17:50:47]

Should we create one instance that is re-used each time? Seems like it would be
faster than creating a new instance.

[danrubel, 2014/02/26 20:10:01]

Good idea. Done.

+    socket.add(encoder.convert(request.toJson()));
+  }
+
+  @override
   void sendResponse(Response response) {
     JsonEncoder encoder = const JsonEncoder(null);
     socket.add(encoder.convert(response.toJson()));