Preheat oven to 375F. In bowl, combine butter, herbs and garlic. With fingertips, rub butter mixture under chicken skin. Season with 1/2 tsp. Salt and pepper. Roast 1 hour. In small cup, combine 1/4 cup each wine and water. Baste bird with mixture. Surround with onion. Continue roasting 45 minutes more or until meat thermometer registers 185F. Remove chicken to serving plate. Skim fat from drippings. Pour juices and onions into food processor; blend until smooth. Pour into saucepan; stir in flour, remaining 1 tbsp wine and 1/4 tsp. Salt. Bring to boil over medium heat until gravy thickens; serve with chicken.