It is time.

ui/wm/core/visibility_controller.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_WM_CORE_VISIBILITY_CONTROLLER_H_
-#define UI_WM_CORE_VISIBILITY_CONTROLLER_H_
-
-#include "base/compiler_specific.h"
-#include "base/logging.h"
-#include "ui/aura/client/visibility_client.h"
-#include "ui/wm/wm_export.h"
-
-namespace wm {
-
-class WM_EXPORT VisibilityController
-    : public aura::client::VisibilityClient {
- public:
-  VisibilityController();
-  virtual ~VisibilityController();
-
- protected:
-  // Subclasses override if they want to call a different implementation of
-  // this function.
-  // TODO(beng): potentially replace by an actual window animator class in
-  //             window_animations.h.
-  virtual bool CallAnimateOnChildWindowVisibilityChanged(aura::Window* window,
-                                                         bool visible);
-
- private:
-  // Overridden from aura::client::VisibilityClient:
-  virtual void UpdateLayerVisibility(aura::Window* window,
-                                     bool visible) override;
-
-  DISALLOW_COPY_AND_ASSIGN(VisibilityController);
-};
-
-// Suspends the animations for visibility changes during the lifetime of an
-// instance of this class.
-//
-// Example:
-//
-// void ViewName::UnanimatedAction() {
-//   SuspendChildWindowVisibilityAnimations suspend(parent);
-//   // Perform unanimated action here.
-//   // ...
-//   // When the method finishes, visibility animations will return to their
-//   // previous state.
-// }
-//
-class WM_EXPORT SuspendChildWindowVisibilityAnimations {
- public:
-  // Suspend visibility animations of child windows.
-  explicit SuspendChildWindowVisibilityAnimations(aura::Window* window);
-
-  // Restore visibility animations to their original state.
-  ~SuspendChildWindowVisibilityAnimations();
-
- private:
-  // The window to manage.
-  aura::Window* window_;
-
-  // Whether the visibility animations on child windows were originally enabled.
-  const bool original_enabled_;
-
-  DISALLOW_COPY_AND_ASSIGN(SuspendChildWindowVisibilityAnimations);
-};
-
-// Tells |window| to animate visibility changes to its children.
-void WM_EXPORT SetChildWindowVisibilityChangesAnimated(
-    aura::Window* window);
-
-}  // namespace wm
-
-#endif  // UI_WM_CORE_VISIBILITY_CONTROLLER_H_