Handle other modes than "view" when configuring widget mode on tabs

Steps to reproduce:

• in a tab, add a widget of type "layout" and fill the layout to use
• in its advanced mode configuration, fill "# {currentUser.isMemberOf('administrators')?'edit':'view'}

  "

=> when an admin user displays the tab, an error occurs

The error occurs because the layout to use is only filled in view mode, not in edit mode => the "edit properties" tab should appear when configuring mode on widgets in tabs.