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

mojo/embedder/embedder.cc

 // Copyright 2014 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/embedder/embedder.h"
 
 #include "base/bind.h"
 #include "base/location.h"
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
@@ skipping 26 matching lines @@
 
   // Create and initialize a |system::Channel|.
   channel_info->channel = new system::Channel();
   bool success = channel_info->channel->Init(
       system::RawChannel::Create(platform_handle.Pass()));
   DCHECK(success);
 
   // Attach the message pipe endpoint.
   system::MessageInTransit::EndpointId endpoint_id =
       channel_info->channel->AttachMessagePipeEndpoint(message_pipe, 1);
+  // We shouldn't get |kInvalidEndpointId| here -- since |CreateChannel()| is
+  // responsible for the local endpoint, and won't close it.
   DCHECK_EQ(endpoint_id, system::Channel::kBootstrapEndpointId);
   success = channel_info->channel->RunMessagePipeEndpoint(
       system::Channel::kBootstrapEndpointId,
       system::Channel::kBootstrapEndpointId);
   DCHECK(success);  // This shouldn't fail.
 
   // Hand the channel back to the embedder.
   if (callback_thread_task_runner) {
     callback_thread_task_runner->PostTask(FROM_HERE,
                                           base::Bind(callback,
@@ skipping 32 matching lines @@
 
 void DestroyChannelOnIOThread(ChannelInfo* channel_info) {
   DCHECK(channel_info);
   DCHECK(channel_info->channel.get());
   channel_info->channel->Shutdown();
   delete channel_info;
 }
 
 }  // namespace embedder
 }  // namespace mojo