I've got a branch of Nashorn (Oracle's Javascript runtime which will be included in OpenJDK 8) modified to build with Java 7. It passes 100% of the ECMA-262 tes

I've got a branch of Nashorn (Oracle's Javascript runtime which will be included in OpenJDK 8) modified to build with Java 7. It passes 100% of the ECMA-262 test suite and you can grab it at http://github.com/furosys/nashorn http://github.com/furosys/nashorn Nashorn would let you get rid of the Javascript Protobufs implementation and use the Java library from Google, among other potential optimizations.