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

net/socket/socks_client_socket.h

Index: net/socket/socks_client_socket.h
diff --git a/net/socket/socks_client_socket.h b/net/socket/socks_client_socket.h
index fb88cd2895a780fef95c1cba015f5be3b1a51e9e..8dfd773b38f6b6596cd15a745af39c4ce217200d 100644
--- a/net/socket/socks_client_socket.h
+++ b/net/socket/socks_client_socket.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// 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.
 
@@ -59,6 +59,7 @@ class NET_EXPORT_PRIVATE SOCKSClientSocket : public StreamSocket {
   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,