Fix widget name collision when generated while adding a widget in a content view's column

How to reproduce:

• create a new schema schema1 and add a property string named nature
• add schema schema1 to document type File
• in content view DefaultContentListingInNavigation (or any content view listing File documents)
  • under Additional result columns, add a column and add the widget Widget by property for property dublincore:nature to it, a single directory suggestion widget is added
    
  • under Resut columns, add a column and add the widget Widget by property for property schema1:nature to it, a widget of type text is added
    
• deploy
• create a document of type File in a Workspace (using the above content view) and set value of schema1:nature to fax
• go back parent Workspace

Pproperty schema1:nature is rendered with a single directory suggestion widget, not a text widget.