Add FlushForTesting to InterfacePtr and Binding.

mojo/public/cpp/bindings/lib/validation_util.h

Index: mojo/public/cpp/bindings/lib/validation_util.h
diff --git a/mojo/public/cpp/bindings/lib/validation_util.h b/mojo/public/cpp/bindings/lib/validation_util.h
index 124e9e69698cd7722082c84cf57463490cd5bc47..c108857d771dc5a3dc7e4cfd1b5a6e85fd6b511a 100644
--- a/mojo/public/cpp/bindings/lib/validation_util.h
+++ b/mojo/public/cpp/bindings/lib/validation_util.h
@@ -78,13 +78,6 @@ bool ValidateMessagePayload(const Message* message,
   return ParamsType::Validate(message->payload(), validation_context);
 }
 
-// The following methods validate control messages defined in
-// interface_control_messages.mojom.
-bool ValidateControlRequest(const Message* message,
-                            ValidationContext* validation_context);
-bool ValidateControlResponse(const Message* message,
-                             ValidationContext* validation_context);
-
 // The following Validate.*NonNullable() functions validate that the given
 // |input| is not null/invalid.
 template <typename T>
@@ -172,6 +165,11 @@ bool ValidateHandleOrInterface(const Interface_Data& input,
 bool ValidateHandleOrInterface(const Handle_Data& input,
                                ValidationContext* validation_context);
 
+class ControlMessageValidator : public MessageReceiver {
+ public:
+  bool Accept(Message* message) override;
+};
+
 }  // namespace internal
 }  // namespace mojo