[cast_channel] Implement CastSocketService::OpenSocket()

extensions/browser/api/cast_channel/cast_channel_api.h

 // 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.
 
 #ifndef EXTENSIONS_BROWSER_API_CAST_CHANNEL_CAST_CHANNEL_API_H_
 #define EXTENSIONS_BROWSER_API_CAST_CHANNEL_CAST_CHANNEL_API_H_
 
 #include <memory>
 #include <string>
 
@@ skipping 156 matching lines @@
     scoped_refptr<cast_channel::Logger> logger_;
 
     DISALLOW_COPY_AND_ASSIGN(CastMessageHandler);
   };
 
   // Validates that |connect_info| represents a valid IP end point and returns a
   // new IPEndPoint if so.  Otherwise returns nullptr.
   static net::IPEndPoint* ParseConnectInfo(
       const api::cast_channel::ConnectInfo& connect_info);
 
-  void OnOpen(cast_channel::ChannelError result);
+  void OnOpen(int channel_id, cast_channel::ChannelError result);
 
   std::unique_ptr<api::cast_channel::Open::Params> params_;
-  // The id of the newly opened socket.
-  int new_channel_id_;
   CastChannelAPI* api_;
   std::unique_ptr<net::IPEndPoint> ip_endpoint_;
   cast_channel::ChannelAuthType channel_auth_;
   base::TimeDelta liveness_timeout_;
   base::TimeDelta ping_interval_;
 
   FRIEND_TEST_ALL_PREFIXES(CastChannelOpenFunctionTest, TestParseConnectInfo);
   DISALLOW_COPY_AND_ASSIGN(CastChannelOpenFunction);
 };
 
@@ skipping 37 matching lines @@
 
   std::unique_ptr<api::cast_channel::Close::Params> params_;
   CastChannelAPI* api_;
 
   DISALLOW_COPY_AND_ASSIGN(CastChannelCloseFunction);
 };
 
 }  // namespace extensions
 
 #endif  // EXTENSIONS_BROWSER_API_CAST_CHANNEL_CAST_CHANNEL_API_H_