DrawRectGradient
virtual void DrawRectGradient(const BRect& rect, BGradient& gradient, bool fill) {}
callbacks.DrawRectGradient(*rect, *gradient,
virtual void DrawRectGradient(const BRect& rect, BGradient& gradient, bool fill);
virtual void DrawRectGradient(const BRect& rect, BGradient& gradient, bool fill);
DrawRectGradient(rect, gradient, fill);
virtual void DrawRectGradient(const BRect& rect, BGradient& gradient, bool fill);