SerialTapDownDetails constructor
- Offset globalPosition = Offset.zero,
 - Offset? localPosition,
 - required PointerDeviceKind kind,
 - int buttons = 0,
 - int count = 1,
 
Creates details for a GestureSerialTapDownCallback.
The count argument must be greater than zero.
Implementation
SerialTapDownDetails({
  this.globalPosition = Offset.zero,
  Offset? localPosition,
  required this.kind,
  this.buttons = 0,
  this.count = 1,
}) : assert(count > 0),
     localPosition = localPosition ?? globalPosition;