TrackingBounds
virtual BRect TrackingBounds(BView* withinView);
if (manipulator->TrackingBounds(fView).Contains(where)
if (fPreviousManipulator->TrackingBounds(fView).Contains(where)
virtual BRect TrackingBounds(BView* withinView);
virtual BRect TrackingBounds(BView* withinView);
virtual BRect TrackingBounds(BView* withinView);