app_list: Moved FolderImageSource into folder_image.cc.

ui/app_list/folder_image_source.h

-// Copyright 2014 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_APP_LIST_APP_LIST_FOLDER_IMAGE_SOURCE_H_
-#define UI_APP_LIST_APP_LIST_FOLDER_IMAGE_SOURCE_H_
-
-#include <vector>
-
-#include "ui/gfx/image/canvas_image_source.h"
-
-namespace gfx {
-class Canvas;
-class ImageSkia;
-class Rect;
-class Size;
-}
-
-namespace app_list {
-
-// Generates the folder icon with the top 4 child item icons laid in 2x2 tile.
-class FolderImageSource : public gfx::CanvasImageSource {
- public:
-  typedef std::vector<gfx::ImageSkia> Icons;
-
-  FolderImageSource(const Icons& icons, const gfx::Size& size);
-  ~FolderImageSource() override;
-
-  // Gets the size of a small app icon inside the folder icon.
-  static gfx::Size ItemIconSize();
-
-  // Calculates the top item icons' bounds inside |folder_icon_bounds|.
-  // Returns the bounds of top item icons in sequence of top left, top right,
-  // bottom left, bottom right.
-  static std::vector<gfx::Rect> GetTopIconsBounds(
-      const gfx::Rect& folder_icon_bounds);
-
- private:
-  void DrawIcon(gfx::Canvas* canvas,
-                const gfx::ImageSkia& icon,
-                const gfx::Size icon_size,
-                int x,
-                int y);
-
-  // gfx::CanvasImageSource overrides:
-  void Draw(gfx::Canvas* canvas) override;
-
-  Icons icons_;
-  gfx::Size size_;
-
-  DISALLOW_COPY_AND_ASSIGN(FolderImageSource);
-};
-
-}  // namespace app_list
-
-#endif  // UI_APP_LIST_APP_LIST_FOLDER_ITEM_H_