aura: Unify WindowTreeHost for some platforms

ui/aura/window_tree_host_win.h

-// Copyright (c) 2012 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.
-
-#ifndef UI_AURA_WINDOW_TREE_HOST_WIN_H_
-#define UI_AURA_WINDOW_TREE_HOST_WIN_H_
-
-#include "base/compiler_specific.h"
-#include "base/memory/scoped_ptr.h"
-#include "ui/aura/aura_export.h"
-#include "ui/aura/window_tree_host.h"
-#include "ui/platform_window/platform_window.h"
-#include "ui/platform_window/platform_window_delegate.h"
-
-namespace aura {
-
-class AURA_EXPORT WindowTreeHostWin
-    : public WindowTreeHost,
-      public NON_EXPORTED_BASE(ui::PlatformWindowDelegate) {
- public:
-  explicit WindowTreeHostWin(const gfx::Rect& bounds);
-  ~WindowTreeHostWin() override;
-
-  // WindowTreeHost:
-  ui::EventSource* GetEventSource() override;
-  gfx::AcceleratedWidget GetAcceleratedWidget() override;
-  void ShowImpl() override;
-  void HideImpl() override;
-  gfx::Rect GetBounds() const override;
-  void SetBounds(const gfx::Rect& bounds) override;
-  gfx::Point GetLocationOnNativeScreen() const override;
-  void SetCapture() override;
-  void ReleaseCapture() override;
-  void SetCursorNative(gfx::NativeCursor cursor) override;
-  void MoveCursorToNative(const gfx::Point& location) override;
-  void OnCursorVisibilityChangedNative(bool show) override;
-
- protected:
-  gfx::AcceleratedWidget hwnd() const { return widget_; }
-
- private:
-  // ui::PlatformWindowDelegate:
-  void OnBoundsChanged(const gfx::Rect& new_bounds) override;
-  void OnDamageRect(const gfx::Rect& damaged_region) override;
-  void DispatchEvent(ui::Event* event) override;
-  void OnCloseRequest() override;
-  void OnClosed() override;
-  void OnWindowStateChanged(ui::PlatformWindowState new_state) override;
-  void OnLostCapture() override;
-  void OnAcceleratedWidgetAvailable(gfx::AcceleratedWidget widget,
-                                    float device_pixel_ratio) override;
-  void OnActivationChanged(bool active) override;
-
-  bool has_capture_;
-  gfx::Rect bounds_;
-  gfx::AcceleratedWidget widget_;
-  scoped_ptr<ui::PlatformWindow> window_;
-
-  DISALLOW_COPY_AND_ASSIGN(WindowTreeHostWin);
-};
-
-}  // namespace aura
-
-#endif  // UI_AURA_WINDOW_TREE_HOST_WIN_H_