I'm in ubuntu 14.04 and my trackpad gives me pixel perfect scrolling in all the native apps, but not Chrome or LibreOffice, I've tried the chrome://flags smooth scrolling option, but that just animates the frankly massive jumps that scrolling gives, extensions and apps do the same thing, is there anything I can do? Do any Other browsers support it?
Regarding your first question, I don't know. As you have stated, there are libraries in Linux which support pixel perfect scrolling, so I suppose it is up to the developers to decide to use them.
As to your second question, the only browser in Linux that I've come across that supports true smooth scrolling is Epiphany (sometimes called "Web").