Move shadow code to views\corewm

ash/wm/shadow.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 ASH_WM_SHADOW_H_
-#define ASH_WM_SHADOW_H_
-
-#include "ash/ash_export.h"
-#include "base/basictypes.h"
-#include "base/memory/scoped_ptr.h"
-#include "ui/compositor/layer_animation_observer.h"
-#include "ui/gfx/rect.h"
-
-namespace ui {
-class Layer;
-}  // namespace ui
-
-namespace ash {
-namespace internal {
-
-class ImageGrid;
-
-// Simple class that draws a drop shadow around content at given bounds.
-class ASH_EXPORT Shadow : public ui::ImplicitAnimationObserver {
- public:
-  enum Style {
-    // Active windows have more opaque shadows, shifted down to make the window
-    // appear "higher".
-    STYLE_ACTIVE,
-
-    // Inactive windows have less opaque shadows.
-    STYLE_INACTIVE,
-
-    // Small windows like tooltips and context menus have lighter, smaller
-    // shadows.
-    STYLE_SMALL,
-  };
-
-  Shadow();
-  virtual ~Shadow();
-
-  void Init(Style style);
-
-  // Returns |image_grid_|'s ui::Layer.  This is exposed so it can be added to
-  // the same layer as the content and stacked below it.  SetContentBounds()
-  // should be used to adjust the shadow's size and position (rather than
-  // applying transformations to this layer).
-  ui::Layer* layer() const;
-
-  const gfx::Rect& content_bounds() const { return content_bounds_; }
-  Style style() const { return style_; }
-
-  // Moves and resizes |image_grid_| to frame |content_bounds|.
-  void SetContentBounds(const gfx::Rect& content_bounds);
-
-  // Sets the shadow's style, animating opacity as necessary.
-  void SetStyle(Style style);
-
-  // ui::ImplicitAnimationObserver overrides:
-  virtual void OnImplicitAnimationsCompleted() OVERRIDE;
-
- private:
-  // Updates the |image_grid_| images to the current |style_|.
-  void UpdateImagesForStyle();
-
-  // Updates the |image_grid_| bounds based on its image sizes and the
-  // current |content_bounds_|.
-  void UpdateImageGridBounds();
-
-  // The current style, set when the transition animation starts.
-  Style style_;
-
-  scoped_ptr<ImageGrid> image_grid_;
-
-  // Bounds of the content that the shadow encloses.
-  gfx::Rect content_bounds_;
-
-  DISALLOW_COPY_AND_ASSIGN(Shadow);
-};
-
-}  // namespace internal
-}  // namespace ash
-
-#endif  // ASH_WM_SHADOW_H_