Mojo Channel: Fix deferred proxy dispatch; support paused channels

ipc/ipc_message_pipe_reader.cc

Index: ipc/ipc_message_pipe_reader.cc
diff --git a/ipc/ipc_message_pipe_reader.cc b/ipc/ipc_message_pipe_reader.cc
index 8e00d5c7b272e1a4a9795ce8802844f4d3d12601..a20489bb41107cac098cdcdfc464c590c13c21b8 100644
--- a/ipc/ipc_message_pipe_reader.cc
+++ b/ipc/ipc_message_pipe_reader.cc
@@ -21,36 +21,6 @@
 namespace IPC {
 namespace internal {
 
-namespace {
-
-// Used by Send() to capture a serialized Channel::Receive message.
-class MessageSerializer : public mojo::MessageReceiverWithResponder {
- public:
-  MessageSerializer() {}
-  ~MessageSerializer() override {}
-
-  mojo::Message* message() { return &message_; }
-
- private:
-  // mojo::MessageReceiverWithResponder
-  bool Accept(mojo::Message* message) override {
-    message_ = std::move(*message);
-    return true;
-  }
-
-  bool AcceptWithResponder(mojo::Message* message,
-                           mojo::MessageReceiver* responder) override {
-    NOTREACHED();
-    return false;
-  }
-
-  mojo::Message message_;
-
-  DISALLOW_COPY_AND_ASSIGN(MessageSerializer);
-};
-
-}  // namespace
-
 MessagePipeReader::MessagePipeReader(
     mojo::MessagePipeHandle pipe,
     mojom::ChannelAssociatedPtr sender,
@@ -58,9 +28,7 @@ MessagePipeReader::MessagePipeReader(
     MessagePipeReader::Delegate* delegate)
     : delegate_(delegate),
       sender_(std::move(sender)),
-      binding_(this, std::move(receiver)),
-      sender_interface_id_(sender_.interface_id()),
-      sender_pipe_(pipe) {
+      binding_(this, std::move(receiver)) {
   sender_.set_connection_error_handler(
       base::Bind(&MessagePipeReader::OnPipeError, base::Unretained(this),
                  MOJO_RESULT_FAILED_PRECONDITION));
@@ -97,20 +65,13 @@ bool MessagePipeReader::Send(std::unique_ptr<Message> message) {
             reinterpret_cast<const uint8_t*>(message->data()) + message->size(),
             data.data());
 
-  MessageSerializer serializer;
-  mojom::ChannelProxy proxy(&serializer);
-  proxy.Receive(data, std::move(handles));
-  mojo::Message* mojo_message = serializer.message();
-
-  size_t num_handles = mojo_message->handles()->size();
-  DCHECK_LE(num_handles, std::numeric_limits<uint32_t>::max());
+  if (!sender_)
+    return false;
 
-  mojo_message->set_interface_id(sender_interface_id_);
-  result = mojo::WriteMessageNew(sender_pipe_, mojo_message->TakeMojoMessage(),
-                                 MOJO_WRITE_MESSAGE_FLAG_NONE);
+  sender_->Receive(data, std::move(handles));
 
   DVLOG(4) << "Send " << message->type() << ": " << message->size();
-  return result == MOJO_RESULT_OK;
+  return true;
 }
 
 void MessagePipeReader::GetRemoteInterface(