It is time.

ui/compositor/layer_delegate.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_COMPOSITOR_LAYER_DELEGATE_H_
-#define UI_COMPOSITOR_LAYER_DELEGATE_H_
-
-#include "base/callback_forward.h"
-#include "ui/compositor/compositor_export.h"
-
-namespace gfx {
-class Canvas;
-class Rect;
-}
-
-namespace ui {
-
-// A delegate interface implemented by an object that renders to a Layer.
-class COMPOSITOR_EXPORT LayerDelegate {
- public:
-  // Paint content for the layer to the specified canvas. It has already been
-  // clipped to the Layer's invalid rect.
-  virtual void OnPaintLayer(gfx::Canvas* canvas) = 0;
-
-  // A notification that this layer has had a delegated frame swap and
-  // will be repainted.
-  virtual void OnDelegatedFrameDamage(const gfx::Rect& damage_rect_in_dip) = 0;
-
-  // Called when the layer's device scale factor has changed.
-  virtual void OnDeviceScaleFactorChanged(float device_scale_factor) = 0;
-
-  // Invoked prior to the bounds changing. The returned closured is run after
-  // the bounds change.
-  virtual base::Closure PrepareForLayerBoundsChange() = 0;
-
- protected:
-  virtual ~LayerDelegate() {}
-};
-
-}  // namespace ui
-
-#endif  // UI_COMPOSITOR_LAYER_DELEGATE_H_