The problem with jvm in the browser is that:

1. Java applets aren't automatically run, you have to click an 'run' button

2. Java can't interact with DOM

JS is built on top of the DOM, and it runs automatically on page load. All JAVAWS has access to is a given section of screen. Honestly, I wish it happens, but I doubt it does. I think chrome would want WASM to succeed and to make everything compile to it because it's a platform they have a significant amount of control over. Which is a damn shame because the JVM is pretty much the best vm out there, and it makes more sense to support it than to try to play catch-up with another VM.