Errors are thrown when deleting VFX and Subgraph assets

How to reproduce:

1. Import the attached package
2. Open scene
3. Open Subgraph and main Graph side by side
4. Select main graph and subgraph in the Project Browse, and delete it

Errors are thrown:

NullReferenceException: Object reference not set to an instance of an object
UnityEditor.VFX.UI.VFXComponentBoard.UpdateBoundsRecorder () (at C:/Users/vitaskruibyte/Documents/unity/packages/com.unity.visualeffectgraph/Editor/GraphView/VFXComponentBoard.cs:371)
UnityEditor.VFX.UI.VFXComponentBoard.UnityEditor.VFX.UI.IControlledElement.OnControllerChanged (UnityEditor.VFX.UI.ControllerChangedEvent& e) (at C:/Users/vitaskruibyte/Documents/unity/packages/com.unity.visualeffectgraph/Editor/GraphView/VFXComponentBoard.cs:725)
UnityEditor.VFX.UI.Controller.NotifyEventHandler (UnityEditor.VFX.UI.IControlledElement eventHandler, System.Int32 eventID) (at C:/Users/vitaskruibyte/Documents/unity/packages/com.unity.visualeffectgraph/Editor/GraphView/Controllers/Controller.cs:73)

 

Note:  unsure if it is a regression