ui: Cleanup class/struct forward declarations

ui/app_list/views/apps_grid_view_folder_delegate.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_VIEWS_APPS_GRID_VIEW_FOLDER_DELEGATE_H_
 #define UI_APP_LIST_VIEWS_APPS_GRID_VIEW_FOLDER_DELEGATE_H_
 
 #include "ui/app_list/app_list_export.h"
 #include "ui/app_list/views/apps_grid_view.h"
 
 namespace gfx {
 class Point;
 }
 
-namespace ui {
-class LocatedEvent;
-}
-
 namespace app_list {
 
 class AppListItemView;
 
 // A delegate which allows an AppsGridView to communicate with its host folder.
 class APP_LIST_EXPORT AppsGridViewFolderDelegate {
  public:
   // Updates the folder view background to show or hide folder container ink
   // bubble.
   virtual void UpdateFolderViewBackground(bool show_bubble) = 0;
@@ skipping 31 matching lines @@
   // synchronous drag has an icon for reparenting while it loads.
   virtual void SetRootLevelDragViewVisible(bool visible) = 0;
 
  protected:
   virtual ~AppsGridViewFolderDelegate() {}
 };
 
 }  // namespace app_list
 
 #endif  // UI_APP_LIST_VIEWS_APPS_GRID_VIEW_FOLDER_DELEGATE_H_