Fixes as per Ram's review

Code/Framework/AzToolsFramework/AzToolsFramework/Entity/PrefabEditorEntityOwnershipInterface.h

@@ -38,7 +38,8 @@ namespace AzToolsFramework
             AZ::IO::PathView filePath, Prefab::InstanceOptionalReference instanceToParentUnder = AZStd::nullopt) = 0;
 
         //! Instantiate the prefab file provided.
-        //! /param entityToParentUnder The entity the newly created prefab instance is parented under.
+        //! /param filePath The filepath for the prefab file the instance should be created from.
+        //! /param instanceToParentUnder The instance the newly instantiated prefab instance is parented under.
         //! /return The optional reference to the prefab instance.
         virtual Prefab::InstanceOptionalReference InstantiatePrefab(
             AZ::IO::PathView filePath, Prefab::InstanceOptionalReference instanceToParentUnder = AZStd::nullopt) = 0;

Code/Framework/AzToolsFramework/AzToolsFramework/Entity/PrefabEditorEntityOwnershipService.cpp

@@ -53,10 +53,6 @@ namespace AzToolsFramework
         AZ_Assert(m_loaderInterface != nullptr,
             "Couldn't get prefab loader interface, it's a requirement for PrefabEntityOwnership system to work");
 
-        m_instanceEntityMapperInterface = AZ::Interface<Prefab::InstanceEntityMapperInterface>::Get();
-        AZ_Assert(m_instanceEntityMapperInterface != nullptr,
-            "Couldn't get instance entity mapper interface, it's a requirement for PrefabEntityOwnership system to work");
-
         m_rootInstance = AZStd::unique_ptr<Prefab::Instance>(m_prefabSystemComponent->CreatePrefab({}, {}, "NewLevel.prefab"));
 
         m_sliceOwnershipService.BusConnect(m_entityContextId);
@@ -325,9 +321,7 @@ namespace AzToolsFramework
             }
 
             Prefab::Instance& addedInstance = instanceToParentUnder->get().AddInstance(AZStd::move(createdPrefabInstance));
-            AZ::Entity* containerEntity = addedInstance.m_containerEntity.get();
-            HandleEntitiesAdded({containerEntity});
-
+            HandleEntitiesAdded({addedInstance.m_containerEntity.get()});
             return addedInstance;
         }
 

Code/Framework/AzToolsFramework/AzToolsFramework/Entity/PrefabEditorEntityOwnershipService.h

@@ -25,7 +25,6 @@ namespace AzToolsFramework
     namespace Prefab
     {
         class Instance;
-        class InstanceEntityMapperInterface;
         class PrefabSystemComponentInterface;
         class PrefabLoaderInterface;
     }
@@ -209,7 +208,6 @@ namespace AzToolsFramework
 
         AZStd::string m_rootPath;
         AZStd::unique_ptr<Prefab::Instance> m_rootInstance;
-        Prefab::InstanceEntityMapperInterface* m_instanceEntityMapperInterface;
         Prefab::PrefabSystemComponentInterface* m_prefabSystemComponent;
         Prefab::PrefabLoaderInterface* m_loaderInterface;
         AzFramework::EntityContextId m_entityContextId;