Use app list item shadow for app list folders.

ui/app_list/views/app_list_item_view.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_APP_LIST_VIEWS_APP_LIST_ITEM_VIEW_H_
 #define UI_APP_LIST_VIEWS_APP_LIST_ITEM_VIEW_H_
 
 #include <string>
 
 #include "base/memory/ref_counted.h"
@@ skipping 26 matching lines @@
                                         public AppListItemObserver,
                                         public ImageShadowAnimator::Delegate {
  public:
   // Internal class name.
   static const char kViewClassName[];
 
   AppListItemView(AppsGridView* apps_grid_view, AppListItem* item);
   ~AppListItemView() override;
 
   // Set the icon of this image, adding a drop shadow if |has_shadow|.
-  void SetIcon(const gfx::ImageSkia& icon, bool has_shadow);
+  void SetIcon(const gfx::ImageSkia& icon);
 
   void SetItemName(const base::string16& display_name,
                    const base::string16& full_name);
   void SetItemIsInstalling(bool is_installing);
   bool is_highlighted() { return is_highlighted_; }  // for unit test
   void SetItemIsHighlighted(bool is_highlighted);
   void SetItemPercentDownloaded(int percent_downloaded);
 
   void Prerender();
 
@@ skipping 114 matching lines @@
 
   // A timer to defer showing drag UI when mouse is pressed.
   base::OneShotTimer<AppListItemView> mouse_drag_timer_;
 
   DISALLOW_COPY_AND_ASSIGN(AppListItemView);
 };
 
 }  // namespace app_list
 
 #endif  // UI_APP_LIST_VIEWS_APP_LIST_ITEM_VIEW_H_