Ch 9. set_user_session is not used

[JunichiIto]

After the chapter 9, set_user_session is not used anymore:

08_features...09_speedup

However it can be used in users_controller_spec:

describe UsersController do
  describe 'user access' do
    before :each do
      @user = create(:user)
      # session[:user_id] = @user.id
      set_user_session(@user)
    end

Please consider to keep on using it or remove it.