Unroll pastry into a 9″ pie plate; flute edges. Brush egg whites over the bottom and sides of the pastry. In a small bowl, combine flour and sugars; cut in butter until mixture resembles fine crumbs. Sprinkle two-thirds into pastry; top with peaches. Sprinkle with remaining crumb mixture. Bake at 375°F for 40–45 minutes or until filling is bubbly and peaches are tender.