(new | edit)_polymorphic_path add to query string

[eval]

Steps to reproduce

# on console
include Rails.application.routes.url_helpers
new_polymorphic_path(User.new)
# => "/users/new?routing_type=path"
edit_polymorphic_path(User.first)
# => => "/users/1/edit?routing_type=path"

Observed: routing_type=path gets added to the query string.
Expected: I expect it to not be there.

PR upcoming.