Mojo C++ bindings: switch device/serial mojom target to use STL types.

device/serial/BUILD.gn

 # Copyright 2014 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.
 
 import("//build/config/features.gni")
 import("//mojo/public/tools/bindings/mojom.gni")
 
 # Library works only on desktop platforms.
 assert(is_win || is_linux || is_mac)
 
@@ skipping 71 matching lines @@
 
 mojom("serial_mojo") {
   visibility = [
     ":serial",
     "//extensions:extensions_renderer_resources_grit",
   ]
 
   sources = [
     "serial.mojom",
   ]
-
-  use_new_wrapper_types = false
 }