Implement Token Binding negotiation TLS extension

net/socket/ssl_client_socket.h

Index: net/socket/ssl_client_socket.h
diff --git a/net/socket/ssl_client_socket.h b/net/socket/ssl_client_socket.h
index 1d38048d0c6bdcf7c6667675a492a9f9929a7616..53170827ec9a185ad6e826d1a880ecb1e9aad76e 100644
--- a/net/socket/ssl_client_socket.h
+++ b/net/socket/ssl_client_socket.h
@@ -158,11 +158,20 @@ class NET_EXPORT SSLClientSocket : public SSLSocket {
       bool channel_id_enabled,
       bool supports_ecc);
 
+  // Records histograms for token binding support during full handshakes.
+  static void RecordTokenBindingSupport(const SSLConfig& ssl_config,
+                                        ChannelIDService* channel_id_service,
+                                        bool negotiated_token_binding);
+
   // Returns whether TLS channel ID is enabled.
   static bool IsChannelIDEnabled(
       const SSLConfig& ssl_config,
       ChannelIDService* channel_id_service);
 
+  // Returns whether Token Binding is enabled.
+  static bool IsTokenBindingEnabled(const SSLConfig& ssl_config,
+                                    ChannelIDService* channel_id_service);
+
   // Determine if there is at least one enabled cipher suite that satisfies
   // Section 9.2 of the HTTP/2 specification.  Note that the server might still
   // pick an inadequate cipher suite.