Steps to reproduce:
Use the following component:
<mx:HBox backgroundColor="haloOrange">
<mx:HSlider minimum="0" maximum="1"/>
</mx:HBox>
Notice it is oversized on the top.
in Slider.as the setters for minimum and maximum set the variable ticksChanged to true which then causes ticks to be created.
commitProperties then checks this:
if (ticksChanged)
{
ticksChanged = false;
createTicks();
}
createTicks blindly creates the ticks. I think the createTicks should be changed to ensure the tickLength style is non zero before creating the ticks.