Whether the overlay's symbols and labels honor the map reference scale when displayed in a map view. If the map has a positive reference scale, and the overlay honors it, then symbols and labels will be drawn at their specified size when the viewing scale is the same as the reference scale. They will grow or shrink as the view zooms in or out to keep the symbol a fixed size on the map. If the map has no reference scale, the reference scale is zero, or GraphicsOverlay.scaleSymbols is false, the symbols and labels will be drawn at their fixed screen size. The default value is 'false'. GraphicsOverlay.scaleSymbols only affects display in a MapView. The symbols and labels will be displayed at fixed screen size in a SceneView.