[Chromoting] Remove DataChannelManagerCallbacks constructor parameter of ClientSession

remoting/host/chromoting_host.cc

 // Copyright (c) 2012 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 "remoting/host/chromoting_host.h"
 
 #include <stddef.h>
 
 #include <algorithm>
 #include <utility>
@@ skipping 245 matching lines @@
         video_encode_task_runner_, audio_task_runner_));
   }
 
   // Create a ClientSession object.
   std::vector<HostExtension*> extension_ptrs;
   for (const auto& extension : extensions_)
     extension_ptrs.push_back(extension.get());
   clients_.push_back(base::MakeUnique<ClientSession>(
       this, std::move(connection), desktop_environment_factory_,
       desktop_environment_options_, max_session_duration_, pairing_registry_,
-      extension_ptrs,
-      std::vector<protocol::DataChannelManager::NameCallbackPair>()));

[jarhar, 2017/07/05 17:51:42]

In order to register callbacks from this file, would you call
ClientSession::RegisterDataChannelManagerCallback() here before adding new
clients to clients_?

like this:
std::unique_ptr<ClientSession> new_client = base::MakeUnique(...);
new_client->RegisterDataChannelManagerCallback(...);
clients_.push_back(std::move(new_client));

[Hzj_jie, 2017/07/05 18:34:31]

That's usually not necessary: Optional data channels and their callbacks won't
take effect before authentication.

+      extension_ptrs));
 }
 
 }  // namespace remoting