Monkey patch action controller in Rails 6.0.0.rc2 to avoid deprecation warning

action_controller_media_type_hack.rb

# Require this in config/application.rb after require "action_controller/railtie"

module ActionController
  module Renderers
    remove :json
    remove :js
    remove :xml

    add :json do |json, options|
      json = json.to_json(options) unless json.kind_of?(String)

      if options[:callback].present?
        if media_type.nil? || media_type == Mime[:json]
          self.content_type = Mime[:js]
        end

        "/**/#{options[:callback]}(#{json})"
      else
        self.content_type = Mime[:json] if media_type.nil?
        json
      end
    end

    add :js do |js, options|
      self.content_type = Mime[:js] if media_type.nil?
      js.respond_to?(:to_js) ? js.to_js(options) : js
    end

    add :xml do |xml, options|
      self.content_type = Mime[:xml] if media_type.nil?
      xml.respond_to?(:to_xml) ? xml.to_xml(options) : xml
    end
  end
end

module ActionController #:nodoc:
  module RequestForgeryProtection
    private

    def non_xhr_javascript_response?
      %r(\A(?:text|application)/javascript).match?(media_type) && !request.xhr?
    end
  end
end