Fix app list drag view being hidden on reparent when synchronous drag is setting up.

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"
 
@@ skipping 35 matching lines @@
   // to the drag_drop_host, eg. dropped on shelf.
   virtual void DispatchEndDragEventForReparent(
       bool events_forwarded_to_drag_drop_host) = 0;
 
   // Returns true if |point| falls outside of the folder container ink bubble.
   virtual bool IsPointOutsideOfFolderBoundary(const gfx::Point& point) = 0;
 
   // Returns true if the associated folder item is an OEM folder.
   virtual bool IsOEMFolder() const = 0;
 
+  // Hides or show the root level's grid view. This is needed so that the
+  // 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_