Remove the InitSubscriber class

Setting to NR for a few days in case anyone wants to comment on why this was added.

Good point, I believe that initially I created the subscriber as the D7 module added the JS with query parameters in hook_init(). after adding the subscriber I apparently went a different route (in JS Alter hook).

Thanks for letting me know, @jrglasgow!

Automatically closed - issue fixed for 2 weeks with no activity.