Error at removing Image on Menu Item

I've attached a new file field to the power menu item where i can upload an image.

If I remove the image, the following error occurs:

Warning: Invalid argument supplied for foreach() in file_field_widget_submit() 
Warning: array_values() expects parameter 1 to be array, null given in file_field_widget_submit()

How to fix:

The problem occurs in funcion power_menu_add_fields_entity_fields() on line 519.
For the field_attach_form(); there must be passed the full $form array instead of $form['power_menu']['fields'].

I'll create a patch.