If you have Visio Professional, open the custom patterns stencil: File > Shapes > Visio Extras > Custom Patterns - Unscaled.
You won't see any shapes on the stencil, but when you go to the Fill dialog, you will see a bunch of named patterns at the bottom of the list.
"Honey" is the one you are looking for.
The white line "isn't really there". For me, it shows and disappears as I vary the zoom--it's a slight rendering bug, I think. I would see if it shows when you print before I worry too much about it.