ui: Move compositor/ directory out of gfx/, up to ui/.

ui/gfx/compositor/layer_delegate.h

-// Copyright (c) 2011 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_GFX_COMPOSITOR_LAYER_DELEGATE_H_
-#define UI_GFX_COMPOSITOR_LAYER_DELEGATE_H_
-#pragma once
-
-#include "ui/gfx/compositor/compositor_export.h"
-
-namespace gfx {
-class Canvas;
-}
-
-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;
-
- protected:
-  virtual ~LayerDelegate() {}
-};
-
-}  // namespace ui
-
-#endif  // UI_GFX_COMPOSITOR_LAYER_DELEGATE_H_