Introduce ash mojo interface for lock screen action handlers

ash/public/interfaces/BUILD.gn

 # Copyright 2015 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")
 
 # Depend upon //ash/public/cpp:ash_public_cpp, which has a public_dep on this.
 # The two targets must be bundled together as the typemaps depend upon
 # //ash/public/cpp, and //ash/public/cpp needs to depend on this for generated
 # code (such as enums and constants).
 mojom("interfaces_internal") {
   visibility = [ "//ash/public/cpp:ash_public_cpp" ]
 
   sources = [
     "accelerator_controller.mojom",
+    "action_handler.mojom",
     "cast_config.mojom",
     "constants.mojom",
     "event_properties.mojom",
     "locale.mojom",
     "media.mojom",
     "new_window.mojom",
     "session_controller.mojom",
     "shelf.mojom",
     "shutdown.mojom",
     "system_tray.mojom",
@@ skipping 11 matching lines @@
     "//mojo/common:common_custom_types",
     "//skia/public/interfaces",
     "//ui/events/mojo:interfaces",
     "//ui/gfx/image/mojo:interfaces",
   ]
 
   export_class_attribute = "ASH_PUBLIC_EXPORT"
   export_define = "ASH_PUBLIC_IMPLEMENTATION=1"
   export_header = "ash/public/cpp/ash_public_export.h"
 }