Use case

My design created his own style range date picker, but since CalendarDateRangePicker class is not exported /material/pickers/pickers.dart (only the function showDateRangePicker) we can use this as a widget, so we can customize, com compose anything with this function.

Proposal

at /material/pickers/pickers.dart
add CalendarDateRangePicker together with showDateRangePicker
dart export 'date_range_picker_dialog.dart' show showDateRangePicker, CalendarDateRangePicker;