I'd much rather use Java, and SWT, which implements native widgets than ship a browser without toolbars. They can even leverage their JS code with Nashorn or Rhino.
SWT is pretty good, and the fact that it uses native widgets makes it great for accessibility. Creating a well-behaved menu bar on OS X was tricky in my experience though. Also, how would you package the app? Ship the full Oracle JRE, or use something more lightweight like Avian?
I work as a web dev, I'm only a hobbyist wrt desktop programming, despite having worked on a small commercial app in Delphi. The toy apps I've built with SWT were tested only on Windows. I didn't even know about Avian - nice reference. But if I had to ship an app, i'd leave it up to the user to install JRE, on the installation instructions.