Manually setting a Flickable's contentY and then flicking sometimes ignores the manually set value

The attached example shows the bug. Click and hold to start manual scrolling, then release and do a regular flick. The flick will cause the view to jump back to where it was before the manual scrolling. This only happens when "interactive" is set to false on the flickable. In the attached example a work-around seems to be to set preventStealing on the child mouse area instead.