/**
 * Instances of [[DevicePixelRatioObserver]] can be registered with a
 * [[DevicePixelRatioMonitor]] to receive callbacks for a change in the HTML window's
 * device pixel ratio.
 */ export default interface DevicePixelRatioObserver { /**
     * Called when the device pixel ratio monitor detects a change in the
     * HTML window's device pixel ratio. This can happen if the window is dragged
     * to a monitor with a different hi-dpi characteristics.
     */ devicePixelRatioChanged ( newDevicePixelRatio ) : void ; }