Preheat oven to 375 degrees F. Place turkey breast, smooth side down, on cutting board. On left breast, cut along right side of tenderloin to separate from breast without cutting tenderloin off; fold tenderloin back. Repeat on right breast, cutting along left side of tenderloin and folding back. Cover surface of turkey with 3 large sheets plastic wrap. With flat side of meat mallet or heavy rolling pin, pound turkey until about 1 inch thick all over. Discard plastic wrap. Sprinkle surface of turkey with 3/4 teaspoon salt. In food processor, pulse green onions, parsley, oil and garlic until finely chopped, stopping to stir occasionally. Spread herb mixture in even layer on breast. Starting with short side, roll breast tightly. Place seam side down. Drape bacon over turkey roll, overlapping slices slightly. Tuck ends of bacon under turkey roll. Using 16-inches pieces of kitchen string, tie turkey tightly at 11/2-inches intervals. (Turkey may be wrapped tightly in plastic and refrigerated up to overnight.) Transfer to rack fitted into roasting pan lined with foil. Add 4 cups water to bottom of pan. Roast 45 minutes. Meanwhile, whisk together sugar, vinegar and syrup. Brush over turkey after it has roasted 45 minutes. Roast another 45 minutes. or until turkey is cooked (internal temperature reaches 160 degrees F), basting with sugar mixture every 15 minutes. Loosely cover with foil; let rest 20 minutes. Cut and discard strings before slicing and serving.