DecoratorFrame
BRect DecoratorFrame() const;
BRect decoratorFrame(DecoratorFrame());
float windowBottom = DecoratorFrame().bottom;
if (Window()->DecoratorFrame().Height() + 2 * TabHeight()
if (Window()->DecoratorFrame().Height() + 2 * TabHeight()
BRect decoratorFrame = DecoratorFrame();
BRect bounds = DecoratorFrame();