WIP: A couple of more ChannelMojo speedup ideas

third_party/mojo/src/mojo/edk/system/message_pipe.h

Index: third_party/mojo/src/mojo/edk/system/message_pipe.h
diff --git a/third_party/mojo/src/mojo/edk/system/message_pipe.h b/third_party/mojo/src/mojo/edk/system/message_pipe.h
index df0501484e5715eb743733b2b739cc77803b49b6..3deee2986a92f9b0b07f06a42603117ad6e2ecb2 100644
--- a/third_party/mojo/src/mojo/edk/system/message_pipe.h
+++ b/third_party/mojo/src/mojo/edk/system/message_pipe.h
@@ -105,6 +105,9 @@ class MOJO_SYSTEM_IMPL_EXPORT MessagePipe : public ChannelEndpointClient {
   void RemoveAwakable(unsigned port,
                       Awakable* awakable,
                       HandleSignalsState* signals_state);
+  MojoResult SetAsyncMessageCallback(unsigned port,
+                                     const AsyncMessageCallback& callback);
+
   void StartSerialize(unsigned port,
                       Channel* channel,
                       size_t* max_size,
@@ -116,7 +119,8 @@ class MOJO_SYSTEM_IMPL_EXPORT MessagePipe : public ChannelEndpointClient {
                     embedder::PlatformHandleVector* platform_handles);
 
   // |ChannelEndpointClient| methods:
-  bool OnReadMessage(unsigned port, MessageInTransit* message) override;
+  bool OnReadMessage(unsigned port,
+                     MessageInTransit::ReadContext& reading_message) override;
   void OnDetachFromChannel(unsigned port) override;
 
  private:
@@ -130,6 +134,10 @@ class MOJO_SYSTEM_IMPL_EXPORT MessagePipe : public ChannelEndpointClient {
                                   scoped_ptr<MessageInTransit> message,
                                   std::vector<DispatcherTransport>* transports);
 
+  MojoResult DispatchOnReadMessageNoLock(
+      unsigned port,
+      MessageInTransit::ReadContext& reading_message);
+
   // Helper for |EnqueueMessageNoLock()|. Must be called with |lock_| held.
   MojoResult AttachTransportsNoLock(
       unsigned port,