Expose Service Describer in Dart mojo package

mojo/dart/packages/mojo_services/lib/mojo/media/media_transport.mojom.dart

Index: mojo/dart/packages/mojo_services/lib/mojo/media/media_transport.mojom.dart
diff --git a/mojo/dart/packages/mojo_services/lib/mojo/media/media_transport.mojom.dart b/mojo/dart/packages/mojo_services/lib/mojo/media/media_transport.mojom.dart
index 01ed709a61234ac331776efde34348b0d14b34d7..1965ce4b25ca7f18dbde414e387324f56bbfc06c 100644
--- a/mojo/dart/packages/mojo_services/lib/mojo/media/media_transport.mojom.dart
+++ b/mojo/dart/packages/mojo_services/lib/mojo/media/media_transport.mojom.dart
@@ -854,11 +854,14 @@ const int _MediaProducer_disconnectName = 1;
 
 
 class _MediaProducerServiceDescription implements service_describer.ServiceDescription {
-  dynamic getTopLevelInterface([Function responseFactory]) => null;
+  dynamic getTopLevelInterface([Function responseFactory]) =>
+      responseFactory(null);
 
-  dynamic getTypeDefinition(String typeKey, [Function responseFactory]) => null;
+  dynamic getTypeDefinition(String typeKey, [Function responseFactory]) =>
+      responseFactory(null);
 
-  dynamic getAllTypeDefinitions([Function responseFactory]) => null;
+  dynamic getAllTypeDefinitions([Function responseFactory]) =>
+      responseFactory(null);
 }
 
 abstract class MediaProducer {
@@ -1084,7 +1087,7 @@ class MediaProducerStub extends bindings.Stub {
 
   int get version => 0;
 
-  service_describer.ServiceDescription get serviceDescription =>
+  static service_describer.ServiceDescription get serviceDescription =>
     new _MediaProducerServiceDescription();
 }
 
@@ -1095,11 +1098,14 @@ const int _MediaPullModeProducer_releasePacketName = 2;
 
 
 class _MediaPullModeProducerServiceDescription implements service_describer.ServiceDescription {
-  dynamic getTopLevelInterface([Function responseFactory]) => null;
+  dynamic getTopLevelInterface([Function responseFactory]) =>
+      responseFactory(null);
 
-  dynamic getTypeDefinition(String typeKey, [Function responseFactory]) => null;
+  dynamic getTypeDefinition(String typeKey, [Function responseFactory]) =>
+      responseFactory(null);
 
-  dynamic getAllTypeDefinitions([Function responseFactory]) => null;
+  dynamic getAllTypeDefinitions([Function responseFactory]) =>
+      responseFactory(null);
 }
 
 abstract class MediaPullModeProducer {
@@ -1383,7 +1389,7 @@ class MediaPullModeProducerStub extends bindings.Stub {
 
   int get version => 0;
 
-  service_describer.ServiceDescription get serviceDescription =>
+  static service_describer.ServiceDescription get serviceDescription =>
     new _MediaPullModeProducerServiceDescription();
 }
 
@@ -1393,11 +1399,14 @@ const int _MediaConsumer_pushPacketName = 1;
 
 
 class _MediaConsumerServiceDescription implements service_describer.ServiceDescription {
-  dynamic getTopLevelInterface([Function responseFactory]) => null;
+  dynamic getTopLevelInterface([Function responseFactory]) =>
+      responseFactory(null);
 
-  dynamic getTypeDefinition(String typeKey, [Function responseFactory]) => null;
+  dynamic getTypeDefinition(String typeKey, [Function responseFactory]) =>
+      responseFactory(null);
 
-  dynamic getAllTypeDefinitions([Function responseFactory]) => null;
+  dynamic getAllTypeDefinitions([Function responseFactory]) =>
+      responseFactory(null);
 }
 
 abstract class MediaConsumer {
@@ -1666,7 +1675,7 @@ class MediaConsumerStub extends bindings.Stub {
 
   int get version => 0;
 
-  service_describer.ServiceDescription get serviceDescription =>
+  static service_describer.ServiceDescription get serviceDescription =>
     new _MediaConsumerServiceDescription();
 }