Initialization error on pass false to tracePositionChange of VertexControl Constructor

[c0nstexpr]

https://github.com/panthernet/GraphX/blob/d4e23495a56196a76c28f2f983f7cf2806cd96c5/GraphX.Controls/Controls/VertexControl.cs#L61 PositionChangeNotification in EventOptions is true by default. Assign false value to it will cause the property call the UpdatePositionTraceState method in VertexControl. Then EventOptions property is used, which is null reference by default, before initialization.