Mojo: Make some attempts towards fixing remote message pipe closure.

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 dd186fd89c4409b9ca8cebde4a3ca4e022a9b6ae..a1a7be3a41502b0fef2247a88bed21d14930f593 100644
--- a/mojo/system/message_pipe_endpoint.cc
+++ b/mojo/system/message_pipe_endpoint.cc
@@ -10,6 +10,10 @@
 namespace mojo {
 namespace system {
 
+void MessagePipeEndpoint::Close() {
+  NOTREACHED();
+}
+
 void MessagePipeEndpoint::CancelAllWaiters() {
   NOTREACHED();
 }
@@ -39,7 +43,12 @@ void MessagePipeEndpoint::Attach(scoped_refptr<Channel> /*channel*/,
   NOTREACHED();
 }
 
-void MessagePipeEndpoint::Run(MessageInTransit::EndpointId /*remote_id*/) {
+bool MessagePipeEndpoint::Run(MessageInTransit::EndpointId /*remote_id*/) {
+  NOTREACHED();
+  return true;
+}
+
+void MessagePipeEndpoint::OnRemove() {
   NOTREACHED();
 }