Mojo: Give ChannelEndpoint the remote ID and ProxyMessagePipeEndpoint the ChannelEndpoint.

mojo/system/message_pipe_endpoint.cc

Index: mojo/system/message_pipe_endpoint.cc
diff --git a/mojo/system/message_pipe_endpoint.cc b/mojo/system/message_pipe_endpoint.cc
index 51f88ec1f7b00cc8e98b254aed62401eee8c099d..a9438361311bafb6cce79f03c86e474c4f944b8d 100644
--- a/mojo/system/message_pipe_endpoint.cc
+++ b/mojo/system/message_pipe_endpoint.cc
@@ -5,7 +5,6 @@
 #include "mojo/system/message_pipe_endpoint.h"
 
 #include "base/logging.h"
-#include "mojo/system/channel.h"
 
 namespace mojo {
 namespace system {
@@ -49,7 +48,8 @@ void MessagePipeEndpoint::RemoveWaiter(Waiter* /*waiter*/,
     *signals_state = HandleSignalsState();
 }
 
-void MessagePipeEndpoint::Attach(scoped_refptr<Channel> /*channel*/,
+void MessagePipeEndpoint::Attach(ChannelEndpoint* /*channel_endpoint*/,
+                                 Channel* /*channel*/,
                                  MessageInTransit::EndpointId /*local_id*/) {
   NOTREACHED();
 }