Fix null pointer bug in thrift_protocol

src/brpc/policy/thrift_protocol.cpp

@@ -232,8 +232,11 @@ void ThriftClosure::DoRun() {
     if (span) {
         span->set_start_send_us(butil::cpuwide_time_us());
     }
-    ScopedMethodStatus method_status(_server->options().thrift_service->_status, 
-                                     _server, &_controller, cpuwide_start_us());
+    Socket* sock = accessor.get_sending_socket();
+    ScopedMethodStatus method_status(
+        server->options().thrift_service ? 
+        server->options().thrift_service->_status : NULL,
+        _server, &_controller, cpuwide_start_us());
     if (!method_status) {
         // Judge errors belongings.
         // may not be accurate, but it does not matter too much.