Add support for OpenSSL Next Protocol Negotiation

net/socket/ssl_client_socket_openssl.h

Index: net/socket/ssl_client_socket_openssl.h
diff --git a/net/socket/ssl_client_socket_openssl.h b/net/socket/ssl_client_socket_openssl.h
index 5e0915a85c2638cbd67d0f19f2296a0dd9ebdbd7..62cc4d43925e04ac91918ee6a8851172a201c3a1 100644
--- a/net/socket/ssl_client_socket_openssl.h
+++ b/net/socket/ssl_client_socket_openssl.h
@@ -6,6 +6,8 @@
 #define NET_SOCKET_SSL_CLIENT_SOCKET_OPENSSL_H_
 #pragma once
 
+#include <string>
+
 #include "base/scoped_ptr.h"
 #include "net/base/cert_verify_result.h"
 #include "net/base/completion_callback.h"
@@ -44,6 +46,10 @@ class SSLClientSocketOpenSSL : public SSLClientSocket {
   // a certificate for this client.
   int ClientCertRequestCallback(SSL* ssl, X509** x509, EVP_PKEY** pkey);
 
+  // Callback from the SSL layer to check which NPN protocol we are supporting
+  int SelectNextProtoCallback(unsigned char** out, unsigned char* outlen,
+                              const unsigned char* in, unsigned int inlen);
+
   // SSLClientSocket methods:
   virtual void GetSSLInfo(SSLInfo* ssl_info);
   virtual void GetSSLCertRequestInfo(SSLCertRequestInfo* cert_request_info);
@@ -146,6 +152,8 @@ class SSLClientSocketOpenSSL : public SSLClientSocket {
     STATE_VERIFY_CERT_COMPLETE,
   };
   State next_handshake_state_;
+  NextProtoStatus npn_status_;
+  std::string npn_proto_;
   BoundNetLog net_log_;
 };