Class names don't get set to change track visibility

[christopherbot]

The main scroll-box div does not get the following class names applied to it when they seemingly should:
.scroll-box--enable-y, .scroll-box--requires-y,
.scroll-box--enable-x, .scroll-box--requires-x.
This causes the tracks to remain invisible and I've had to update my style sheet to check for different class names for this visibility toggle to work. I replaced them with these class names:
scroll-box--has-axis-y, scroll-box--show-axis-y,
scroll-box--has-axis-x, scroll-box--show-axis-x,
but I don't think I should have to.