Variables in widget_dimensions

I have four devices that can all share the same dashboard configurations with a slight change to the widget_dimensions. I’d like to be able to use skin variables, say tile_size_x, tile_size_y, so that my dashboard file would look something like this

widget_dimensions: [$tile_size_x, $tile_size_y]

   - include: $layout

where $layout is either “landscape” or “portrait”, referring to either landscape.yaml or portrait.yaml