Vaadin 7.6.1 shows new JARs yuicompressor and js -- needed on server?

On upgrading from 7.5 to 7.6, I noted that Ivy includes the JAR files js-1.7R2.jar and yuicompressor-2.4.8.jar.

Are these 2 new JARs required for the server deployment in production? I have upgraded the obvious new server JARs jsoup-1.8.3.jar as well as the new vaadin*-7.6.1.jar (already we don’t release vaadin-client-compiled-7.6.1.jar). Or are they just for client side development and not needed on our production server?

I am running a server deployment with those two JARs and it seems to run fine, but you never know if those missing JARs will cause some issue later…