DrawDefaultInspector logic

This is roughly what DrawDefaultInspector() does:

 override def OnInspectorGUI():
     serializedObject.Update()
     EditorGUIUtility.LookLikeInspector()
     myIterator = serializedObject.FindProperty("myArrayField")
     while true:
         myRect = GUILayoutUtility.GetRect(0f, 16f);
         showChildren = EditorGUI.PropertyField(myRect, myIterator)
         break unless myIterator.NextVisible(showChildren)
     serializedObject.ApplyModifiedProperties()