Revert of Finish eliminating PlatformWindowMus

ui/platform_window/stub/stub_window.cc

 // 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.
 
 #include "ui/platform_window/stub/stub_window.h"
 
-#include "ui/gfx/native_widget_types.h"
 #include "ui/platform_window/platform_window_delegate.h"
 
 namespace ui {
 
-StubWindow::StubWindow(
-    PlatformWindowDelegate* delegate, gfx::AcceleratedWidget accelerated_widget)
-    : delegate_(delegate) {
-  delegate_->OnAcceleratedWidgetAvailable(accelerated_widget, 1.f);
+StubWindow::StubWindow(PlatformWindowDelegate* delegate) : delegate_(delegate) {
+  delegate_->OnAcceleratedWidgetAvailable(gfx::kNullAcceleratedWidget, 1.f);
 }
 
 StubWindow::~StubWindow() {
 }
 
 void StubWindow::Show() {
 }
 
 void StubWindow::Hide() {
 }
@@ skipping 40 matching lines @@
 }
 
 void StubWindow::ConfineCursorToBounds(const gfx::Rect& bounds) {
 }
 
 PlatformImeController* StubWindow::GetPlatformImeController() {
   return nullptr;
 }
 
 }  // namespace ui