Preheat oven to 325°. To prepare the cake, with an electric mixer, beat egg whites with salt and cream of tartar until they begin to foam. Add sugar and beat until stiff peaks form. Mix in vanilla. Carefully fold in flour. Pour half of the batter into an ungreased 9-inch tube pan and top with half of the chopped cherries. Pour in the remaining batter and sprinkle on the remaining cherries. Bake for 50 minutes, or until a toothpick comes out clean. Let cool before removing from the pan. To prepare the filling, blend cream cheese and sugar with an electric mixer until smooth. Add half-and-half and pureed cherries. To assemble, cut the cake into 1-inch cubes. In a trifle dish, place an even layer of cake cubes and cheesecake filling. Sprinkle with chopped cherries and shaved chocolate. Repeat layers until the trifle dish is full, finishing with whipped cream and the remaining cherries and chocolate on top.