Add a new GetTlsUniqueChannelBinding method to SSLSocket, and implement nss version.

net/socket/ssl_client_socket_nss.h

Index: net/socket/ssl_client_socket_nss.h
diff --git a/net/socket/ssl_client_socket_nss.h b/net/socket/ssl_client_socket_nss.h
index 434b7c67b90873ec916873cc5773898a12b57983..2437c37c2499855beacbfc0a64453d501663b912 100644
--- a/net/socket/ssl_client_socket_nss.h
+++ b/net/socket/ssl_client_socket_nss.h
@@ -65,14 +65,18 @@ class SSLClientSocketNSS : public SSLClientSocket {
                      const SSLClientSocketContext& context);
   virtual ~SSLClientSocketNSS();
 
-  // SSLClientSocket implementation.
-  virtual void GetSSLCertRequestInfo(
-      SSLCertRequestInfo* cert_request_info) OVERRIDE;
+  // SSLSocket implementation.
   virtual int ExportKeyingMaterial(const base::StringPiece& label,
                                    bool has_context,
                                    const base::StringPiece& context,
                                    unsigned char* out,
                                    unsigned int outlen) OVERRIDE;
+  virtual int GetTlsUniqueChannelBinding(unsigned char* out,
+                                         unsigned int *outlen,
+                                         unsigned int outlen_max) OVERRIDE;
+  // SSLClientSocket implementation.
+  virtual void GetSSLCertRequestInfo(
+      SSLCertRequestInfo* cert_request_info) OVERRIDE;
   virtual NextProtoStatus GetNextProto(std::string* proto,
                                        std::string* server_protos) OVERRIDE;