Remove usages of AnchoredChangedMessage.

It was a component message which is now deprecated.

Content.Server/GameObjects/EntitySystems/Disposal/DisposalMailingUnitSystem.cs

@@ -0,0 +1,30 @@
+using Content.Server.GameObjects.Components.Disposal;
+using Robust.Shared.GameObjects;
+
+namespace Content.Server.GameObjects.EntitySystems.Disposal
+{
+    public sealed class DisposalMailingUnitSystem : EntitySystem
+    {
+        public override void Initialize()
+        {
+            base.Initialize();
+
+            SubscribeLocalEvent<DisposalMailingUnitComponent, PhysicsBodyTypeChangedEvent>(BodyTypeChanged);
+        }
+
+        public override void Shutdown()
+        {
+            base.Shutdown();
+
+            UnsubscribeLocalEvent<DisposalMailingUnitComponent, PhysicsBodyTypeChangedEvent>();
+        }
+
+        private static void BodyTypeChanged(
+            EntityUid uid,
+            DisposalMailingUnitComponent component,
+            PhysicsBodyTypeChangedEvent args)
+        {
+            component.UpdateVisualState();
+        }
+    }
+}