Add classList on View base

[NathanaelA]

One of the items I created way back in NS1 days was adding "classList" to the base view classes so that you can do:
View.classList.toggle("hidden") or View.classList.add("blue"); -- The current NS theme's also re-implements this same code and I've seen a couple other plugins re-implement this. https://developer.mozilla.org/en-US/docs/Web/API/Element/classList -- I would be willing to merge my code from my plugin into core so that this is supported on all elements that have a "class" property.
The actual functions that classList support are documented here as classList is a DomTokenList object:

• https://developer.mozilla.org/en-US/docs/Web/API/DOMTokenList

This is one of the few utility functions that I find so helpful as you can easily add/remove/toggle classes on any element which can be very helpful in highlighting errors, flow, or even starting/stopping animations...

[farfromrefug]

What s the overhead of that on ViewBase? I tend to never use css anymore because it is much faster. Thus my question, what s the overhead in code and perfs of adding classList?

[rigor789]

Likely minimal if even measurable. To my understanding, it would just be a method that manipulates the existing class string (not sure if that's what the plugins do).