Revert "rename context to serialization_context and add url helpers"

lib/active_model/serializer/railtie.rb

@@ -7,18 +7,6 @@ module ActiveModel
       end
     end
 
-    initializer 'active_model_serializers.url_helpers' do
-      ActiveSupport.on_load(:action_controller) do
-        ActiveModelSerializers.url_helpers = Module.new do
-          include Rails.application.routes.url_helpers
-
-          def self.default_url_options
-            ActionController::Base.default_url_options
-          end
-        end
-      end
-    end
-
     initializer 'generators' do |app|
       app.load_generators
       require 'generators/serializer/resource_override'