Updated LOF javascript for layout switches #4959

Switching grid -> list and vice versa updates the display style to only use valid styles.  I updated os_sv_list::entity_view_modes() to be aware of the layout.

The layout select is only visible for images and videos.  However, selecting one of these and then going back to content type would give you content type = audio, layout = grid.  So when that happens I added an event to reset layout to list.

For simplicity's sake, layout changes just trigger the content type change function we already had.