should remove unused support for enabling javac logging

We should remove this usused method. If nothing else, it causes an unnecessary dependency for Jigsaw.

In com.sun.tools.javac.main.JavaCompiler

    public static void enableLogging() {
        Logger logger = Logger.getLogger(com.sun.tools.javac.Main.class.getPackage().getName());
        logger.setLevel(Level.ALL);
        for (Handler h : logger.getParent().getHandlers()) {
            h.setLevel(Level.ALL);
       }

    }