Add a new GetNegotiatedProtocol method to StreamSocket and implement in all subclasses.

net/http/http_proxy_client_socket.h

 // 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.
 
 #ifndef NET_HTTP_HTTP_PROXY_CLIENT_SOCKET_H_
 #define NET_HTTP_HTTP_PROXY_CLIENT_SOCKET_H_
 #pragma once
 
 #include <string>
 
@@ skipping 55 matching lines @@
   virtual void Disconnect() OVERRIDE;
   virtual bool IsConnected() const OVERRIDE;
   virtual bool IsConnectedAndIdle() const OVERRIDE;
   virtual const BoundNetLog& NetLog() const OVERRIDE;
   virtual void SetSubresourceSpeculation() OVERRIDE;
   virtual void SetOmniboxSpeculation() OVERRIDE;
   virtual bool WasEverUsed() const OVERRIDE;
   virtual bool UsingTCPFastOpen() const OVERRIDE;
   virtual int64 NumBytesRead() const OVERRIDE;
   virtual base::TimeDelta GetConnectTimeMicros() const OVERRIDE;
+  virtual NextProto GetNegotiatedProtocol() const OVERRIDE;
 
   // Socket implementation.
   virtual int Read(IOBuffer* buf,
                    int buf_len,
                    const CompletionCallback& callback) OVERRIDE;
   virtual int Write(IOBuffer* buf,
                     int buf_len,
                     const CompletionCallback& callback) OVERRIDE;
   virtual bool SetReceiveBufferSize(int32 size) OVERRIDE;
   virtual bool SetSendBufferSize(int32 size) OVERRIDE;
@@ skipping 73 matching lines @@
   HttpRequestHeaders request_headers_;
 
   const BoundNetLog net_log_;
 
   DISALLOW_COPY_AND_ASSIGN(HttpProxyClientSocket);
 };
 
 }  // namespace net
 
 #endif  // NET_HTTP_HTTP_PROXY_CLIENT_SOCKET_H_