Remove more usage of ItemAdjustments outside of OrderUpdater

core/app/models/spree/order.rb

@@ -511,9 +511,7 @@ def create_proposed_shipments
 
     def apply_free_shipping_promotions
       Spree::PromotionHandler::FreeShipping.new(self).activate
-      shipments.each { |shipment| ItemAdjustments.new(shipment).update }
-      updater.update_shipment_total
-      persist_totals
+      update!
     end
 
     # Clean shipments and make order back to address state

core/app/models/spree/order_contents.rb

@@ -119,7 +119,6 @@ def after_add_or_remove(line_item, options = {})
       shipment = options[:shipment]
       shipment.present? ? shipment.update_amounts : order.ensure_updated_shipments
       PromotionHandler::Cart.new(order, line_item).activate
-      ItemAdjustments.new(line_item).update
       reload_totals
       line_item
     end

core/spec/models/spree/order_spec.rb

@@ -591,16 +591,12 @@ def merge!(other_order, user = nil)
 
   context "#apply_free_shipping_promotions" do
     it "calls out to the FreeShipping promotion handler" do
-      shipment = double('Shipment')
-      allow(order).to receive_messages shipments: [shipment]
-      expect(Spree::PromotionHandler::FreeShipping).to receive(:new).and_return(handler = double)
-      expect(handler).to receive(:activate)
+      expect_any_instance_of(Spree::PromotionHandler::FreeShipping).to(
+        receive(:activate)
+      ).and_call_original
 
-      expect(Spree::ItemAdjustments).to receive(:new).with(shipment).and_return(adjuster = double)
-      expect(adjuster).to receive(:update)
+      expect(order.updater).to receive(:update).and_call_original
 
-      expect(order.updater).to receive(:update_shipment_total)
-      expect(order.updater).to receive(:persist_totals)
       order.apply_free_shipping_promotions
     end
   end