Add FlushForTesting to InterfacePtr and Binding.

mojo/public/cpp/bindings/lib/interface_endpoint_client.cc

Index: mojo/public/cpp/bindings/lib/interface_endpoint_client.cc
diff --git a/mojo/public/cpp/bindings/lib/interface_endpoint_client.cc b/mojo/public/cpp/bindings/lib/interface_endpoint_client.cc
index a79316c0b8232f38c94048461c5276504849070d..8875e02a072f0d5fd9e08225f111ff22aee4d4d5 100644
--- a/mojo/public/cpp/bindings/lib/interface_endpoint_client.cc
+++ b/mojo/public/cpp/bindings/lib/interface_endpoint_client.cc
@@ -17,6 +17,7 @@
 #include "mojo/public/cpp/bindings/associated_group.h"
 #include "mojo/public/cpp/bindings/associated_group_controller.h"
 #include "mojo/public/cpp/bindings/interface_endpoint_controller.h"
+#include "mojo/public/cpp/bindings/lib/validation_util.h"
 #include "mojo/public/cpp/bindings/sync_call_restrictions.h"
 
 namespace mojo {
@@ -134,7 +135,8 @@ InterfaceEndpointClient::InterfaceEndpointClient(
     MessageReceiverWithResponderStatus* receiver,
     std::unique_ptr<MessageReceiver> payload_validator,
     bool expect_sync_requests,
-    scoped_refptr<base::SingleThreadTaskRunner> runner)
+    scoped_refptr<base::SingleThreadTaskRunner> runner,
+    uint32_t interface_version)
     : handle_(std::move(handle)),
       incoming_receiver_(receiver),
       thunk_(this),
@@ -142,6 +144,8 @@ InterfaceEndpointClient::InterfaceEndpointClient(
       next_request_id_(1),
       encountered_error_(false),
       task_runner_(std::move(runner)),
+      control_message_proxy_(this),
+      control_message_handler_(interface_version),
       weak_ptr_factory_(this) {
   DCHECK(handle_.is_valid());
   DCHECK(handle_.is_local());
@@ -149,6 +153,7 @@ InterfaceEndpointClient::InterfaceEndpointClient(
   // TODO(yzshen): the way to use validator (or message filter in general)
   // directly is a little awkward.
   filters_.Append(std::move(payload_validator));
+  filters_.Append(base::MakeUnique<internal::ControlMessageValidator>());

[yzshen1, 2016/08/29 23:24:58]

I took a different approach for pipe-control messages: I didn't add a validator
because that means one extra layer of call for every message, while control
messages are extremely rare.

Instead I explicitly validate control message payload in
pipe_control_message_handler (didn't do it also in pipe_control_message_proxy
because we don't have any response message in that case).

Does that make sense? (I might be a little paranoid. :))

[Sam McNally, 2016/08/30 03:05:51]

Done.

 
   controller_ = handle_.group_controller()->AttachEndpointClient(
       handle_, this, task_runner_);
@@ -275,6 +280,8 @@ void InterfaceEndpointClient::NotifyError() {
   // longer.
   async_responders_.clear();
 
+  control_message_proxy_.OnConnectionError();
+
   if (!error_handler_.is_null())
     error_handler_.Run();
 }
@@ -284,12 +291,19 @@ bool InterfaceEndpointClient::HandleValidatedMessage(Message* message) {
   DCHECK(!encountered_error_);
 
   if (message->has_flag(Message::kFlagExpectsResponse)) {
-    if (!incoming_receiver_)
+    if (!incoming_receiver_ &&

[yzshen1, 2016/08/29 23:24:58]

nit: maybe we could remove this check and let it crash in that case. It should
never happen. (and also line 332)

[Sam McNally, 2016/08/30 03:05:51]

Done. This should never happen because validation will block messages that are
neither responses nor control messages when |!incoming_receiver_|, right?

+        !mojo::internal::ControlMessageHandler::IsControlMessage(message)) {
       return false;
+    }
 
     MessageReceiverWithStatus* responder =
         new ResponderThunk(weak_ptr_factory_.GetWeakPtr(), task_runner_);
-    bool ok = incoming_receiver_->AcceptWithResponder(message, responder);
+    bool ok = false;
+    if (mojo::internal::ControlMessageHandler::IsControlMessage(message)) {
+      ok = control_message_handler_.AcceptWithResponder(message, responder);
+    } else {
+      ok = incoming_receiver_->AcceptWithResponder(message, responder);
+    }
     if (!ok)
       delete responder;
     return ok;
@@ -312,6 +326,9 @@ bool InterfaceEndpointClient::HandleValidatedMessage(Message* message) {
     async_responders_.erase(it);
     return responder->Accept(message);
   } else {
+    if (mojo::internal::ControlMessageHandler::IsControlMessage(message))
+      return control_message_handler_.Accept(message);
+
     if (!incoming_receiver_)
       return false;