Mojo: Minor cleanup (of message_in_transit.cc and message_pipe.*).

mojo/system/channel.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "mojo/system/channel.h"
 
 #include <algorithm>
 
 #include "base/basictypes.h"
 #include "base/bind.h"
@@ skipping 333 matching lines @@
     DVLOG(2) << "Ignoring downstream message for zombie endpoint (local ID = "
              << local_id << ", remote ID = " << message_view.source_id() << ")";
     return;
   }
 
   // We need to duplicate the message, because |EnqueueMessage()| will take
   // ownership of it.
   scoped_ptr<MessageInTransit> message(new MessageInTransit(message_view));
   message->DeserializeDispatchers(this);
   MojoResult result = endpoint_info.message_pipe->EnqueueMessage(
-      MessagePipe::GetPeerPort(endpoint_info.port), message.Pass(), NULL);
+      MessagePipe::GetPeerPort(endpoint_info.port), message.Pass());
   if (result != MOJO_RESULT_OK) {
     // TODO(vtl): This might be a "non-error", e.g., if the destination endpoint
     // has been closed (in an unavoidable race). This might also be a "remote"
     // error, e.g., if the remote side is sending invalid control messages (to
     // the message pipe).
     HandleLocalError(base::StringPrintf(
         "Failed to enqueue message to local ID %u (result %d)",
         static_cast<unsigned>(local_id), static_cast<int>(result)));
     return;
   }
@@ skipping 108 matching lines @@
   // TODO(vtl): Is this how we really want to handle this?
   // Sometimes we'll want to propagate the error back to the message pipe
   // (endpoint), and notify it that the remote is (effectively) closed.
   // Sometimes we'll want to kill the channel (and notify all the endpoints that
   // their remotes are dead.
   LOG(WARNING) << error_message;
 }
 
 }  // namespace system
 }  // namespace mojo