Implement GpuArcVideoService::AcceleratorStub using mojo

components/arc/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")
 
 static_library("arc") {
   sources = [
     "arc_bridge_bootstrap.cc",
     "arc_bridge_bootstrap.h",
@@ skipping 44 matching lines @@
     "common/app.mojom",
     "common/arc_bridge.mojom",
     "common/auth.mojom",
     "common/clipboard.mojom",
     "common/input.mojom",
     "common/notifications.mojom",
     "common/power.mojom",
     "common/process.mojom",
     "common/settings.mojom",
     "common/video.mojom",
+    "common/video_accelerator.mojom",
   ]
 }
 
 static_library("arc_test_support") {
   testonly = true
   sources = [
     "test/fake_app_instance.cc",
     "test/fake_app_instance.h",
     "test/fake_arc_bridge_instance.cc",
     "test/fake_arc_bridge_instance.h",
@@ skipping 23 matching lines @@
     "//chromeos",
     "//ipc/mojo:mojo",
     "//mojo/public/cpp/environment:environment",
     "//mojo/public/cpp/system:system",
     "//testing/gtest",
     "//ui/aura",
     "//ui/events",
     "//ui/events:dom_keycode_converter",
   ]
 }