Upgrade to ECJ 4.2.2

We're currently using ECJ 3.2 which is severely outdated. It is so outdated that we can't even compile the newest version of classpath from git with it (which we need to do when we want to add patches against GNU Classpath).

We should update to a newer version of ECJ. The newest available version is 4.3, but I think we should try 4.2.2 first and see if it works.