Brew MP 1.0.2
Scrollbar can also be used seperately without a child widget.This function
attaches a target widget to scrollbar widget. All Scroll Events
are routed to this target widget if it is set and listens to EVT_MDL_SCROLL_CHANGE
event and invalidates itself.
int IWidget_SetTargetWidget(IWidget *pif, IWidget *pTarget);
AEE_SUCCESS - The widget was able to successfully set target widget
AEE_EFAILED - The widget was unable to set target widget