NullReferenceException errors are thrown on resetting with Simple Heads & Spark template. Unable to assign Asset Template again.

Steps to repro:
1. Create a new project.
2. Window > Package Manager> Visual Effect Graph > Install.
3. GameObject > Visual Effects > Visual Effect.
4. Change Asset Template > Simple Heads & Sparks.
5. Reset.

Actual Result:
NullReferenceException errors are thrown in the console.

Expected Result:
No errors in the console.

Tested with Unity Version: 2020.1.0a14, 2019.3.0b12.

Tested with Package Version: 7.1.5

Environment:
Windows 10 & Mac 10.14.

Stack trace:
NullReferenceException: Object reference not set to an instance of an object
UnityEditor.VFX.AdvancedVisualEffectEditor.EmptyLineControl (System.String name, System.String tooltip, System.Int32 depth) (at Library/PackageCache/com.unity.visualeffectgraph@7.1.5/Editor/Inspector/AdvancedVisualEffectEditor.cs:219)
UnityEditor.VFX.VisualEffectEditor.DrawParameters () (at Library/PackageCache/com.unity.visualeffectgraph@7.1.5/Editor/Inspector/VisualEffectEditor.cs:846)
UnityEditor.VFX.VisualEffectEditor.OnInspectorGUI () (at Library/PackageCache/com.unity.visualeffectgraph@7.1.5/Editor/Inspector/VisualEffectEditor.cs:750)
UnityEditor.VFX.AdvancedVisualEffectEditor.OnInspectorGUI () (at Library/PackageCache/com.unity.visualeffectgraph@7.1.5/Editor/Inspector/AdvancedVisualEffectEditor.cs:143)
UnityEditor.UIElements.InspectorElement+<>c__DisplayClass55_0.<CreateIMGUIInspectorFromEditor>b__0 () (at <cdd38c6cb7c446c6ac90945c7521da61>:0)
UnityEditor.EditorApplication:Internal_CallGlobalEventHandler()