Generate Mojom Types in Dart (Take 2)

mojo/dart/packages/mojo/lib/src/proxy.dart

Index: mojo/dart/packages/mojo/lib/src/proxy.dart
diff --git a/mojo/dart/packages/mojo/lib/src/proxy.dart b/mojo/dart/packages/mojo/lib/src/proxy.dart
index bc388c8bde771eda49b52c02335dcab2d493482f..9ca4f13b79d26c448d7716993107a4f106314352 100644
--- a/mojo/dart/packages/mojo/lib/src/proxy.dart
+++ b/mojo/dart/packages/mojo/lib/src/proxy.dart
@@ -35,6 +35,11 @@ abstract class Proxy extends core.MojoEventHandler {
   /// call to [queryVersion] or [requireVersion] is made.
   int get version => _version;
 
+  /// Returns a service description, which exposes the mojom type information
+  /// of the service being proxied.
+  /// Note: The description is null or incomplete if type info is unavailable.
+  service_describer.ServiceDescription get description => null;
+
   void handleRead() {
     var result = endpoint.queryAndRead();
     if ((result.data == null) || (result.dataLength == 0)) {