added derivable default UI elements editor

com.unity.perception/Editor/Utilities.meta

+fileFormatVersion: 2
+guid: 7c33b05b860544a5a026b97302d0358e
+timeCreated: 1611791860

com.unity.perception/Editor/Utilities/DefaultUIElementsEditor.cs

+using UnityEditor.UIElements;
+using UnityEngine.UIElements;
+
+namespace UnityEngine.Experimental.Perception.Editor
+{
+    /// <summary>
+    /// Derive this class to force the Unity Editor to render an Object's default inspector using UIElements
+    /// </summary>
+    public abstract class DefaultUIElementsEditor : UnityEditor.Editor
+    {
+        public override VisualElement CreateInspectorGUI()
+        {
+            var rootElement = new VisualElement();
+            CreatePropertyFields(rootElement);
+            return rootElement;
+        }
+
+        void CreatePropertyFields(VisualElement rootElement)
+        {
+            var iterator = serializedObject.GetIterator();
+            iterator.NextVisible(true);
+            do
+            {
+                if (iterator.name == "m_Script")
+                    continue;
+                var propertyField = new PropertyField(iterator.Copy());
+                propertyField.Bind(serializedObject);
+                rootElement.Add(propertyField);
+            } while (iterator.NextVisible(false));
+        }
+    }
+}

com.unity.perception/Editor/Utilities/DefaultUIElementsEditor.cs.meta

+fileFormatVersion: 2
+guid: ec638a81755645739ca5834e2e44fc13
+timeCreated: 1611791890