jdk9: fix root loader for java not being a URLClassLoader anymore
jdk9: fix root loader for java not being a URLClassLoader anymore

russel/incubator-groovy,shils/incubator-groovy,jwagenleitner/incubator-groovy,shils/groovy,graemerocher/incubator-groovy,bsideup/incubator-groovy,fpavageau/groovy,shils/groovy,russel/groovy,jwagenleitner/incubator-groovy,russel/incubator-groovy,dpolivaev/groovy,armsargis/groovy,apache/groovy,paulk-asert/incubator-groovy,graemerocher/incubator-groovy,apache/groovy,avafanasiev/groovy,paulk-asert/incubator-groovy,bsideup/incubator-groovy,traneHead/groovy-core,traneHead/groovy-core,armsargis/groovy,shils/groovy,paulk-asert/groovy,apache/incubator-groovy,dpolivaev/groovy,apache/incubator-groovy,jwagenleitner/incubator-groovy,fpavageau/groovy,russel/incubator-groovy,dpolivaev/groovy,russel/incubator-groovy,armsargis/groovy,jwagenleitner/groovy,paulk-asert/groovy,apache/groovy,traneHead/groovy-core,paulk-asert/groovy,fpavageau/groovy,bsideup/incubator-groovy,alien11689/incubator-groovy,traneHead/groovy-core,bsideup/incubator-groovy,russel/groovy,jwagenleitner/groovy,avafanasiev/groovy,dpolivaev/groovy,shils/incubator-groovy,jwagenleitner/groovy,armsargis/groovy,paulk-asert/incubator-groovy,alien11689/incubator-groovy,shils/incubator-groovy,paulk-asert/incubator-groovy,alien11689/incubator-groovy,graemerocher/incubator-groovy,shils/groovy,russel/groovy,avafanasiev/groovy,russel/groovy,shils/incubator-groovy,jwagenleitner/incubator-groovy,avafanasiev/groovy,paulk-asert/groovy,graemerocher/incubator-groovy,paulk-asert/incubator-groovy,apache/groovy,alien11689/incubator-groovy,apache/incubator-groovy,jwagenleitner/groovy,apache/incubator-groovy,fpavageau/groovy