Use OnceCallback on Mojo interfaces in //device/gamepad

device/gamepad/public/interfaces/BUILD.gn

 # Copyright 2016 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("//mojo/public/tools/bindings/mojom.gni")
 
 mojom("interfaces") {
   sources = [
     "gamepad.mojom",
   ]
-
-  # TODO(crbug.com/714018): Convert the implementation to use OnceCallback.
-  use_once_callback = false
 }
 
 mojom("gamepad_struct_traits_test") {
   sources = [
     "gamepad_struct_traits_test.mojom",
   ]
 
   public_deps = [
     ":interfaces",
   ]
-
-  # TODO(crbug.com/714018): Convert the implementation to use OnceCallback.
-  use_once_callback = false
 }