Also to add to what has already been said, you don't need antivirus protection on a chromebook since nothing "executes" on your computer. It's all in the cloud. Servers like Google's servers are scanned all the time and what not, plus your files even if they're infected, it wouldn't matter, you'll be using online editors with the files, they don't "execute" the files even on the server end. They simply parse through the code of the file and recreate it for the browser. Thus even if you had infected files your computer would never get harmed, nor would Google's servers(unless a hacker was extremely clever)