Exposed form formatter

I see no reason not to include this if a suitable patch is provided.

I'll update to add that one of my concerns here would be how we would handle this for displays that weren't page displays. It seems like for this to work, the exposed form would have to be related to a page display that the form could submit to. This could lead to confusing behavior if a user picks a view and display that isn't a page display but has this selected as their formatter.

Given the ease in adding your own field formatters in Drupal 8, I'm going to recommend that you implement this in either a custom module, or a related contrib module. There are a lot of different display formatters that don't provide a route to view the results. To me, that makes it problematic to provide a formatter in the standard module that would only function properly with page displays. The exposed filters would have no where to submit to otherwise, or we'd need a more complicated formatter that took the exposed form and executed the view, returning the results in the same space via ajax. That functionality could be accomplished by configuring the exposed filters to require user input and ensuring that the View had ajax enabled.

If you do create a extensions module with a formatter for this, please let me know and I'll be happy to link to it on the project page.