Try to use a more current java 9 for travis ci
Try to use a more current java 9 for travis ci

git-svn-id: https://svn.apache.org/repos/asf/jmeter/trunk@1823891 13f79535-47bb-0310-9956-ffa450edef68

Former-commit-id: 7488b2cb3c9de4fae18875e2ae138e3e3a141860
benbenw/jmeter,ham1/jmeter,ham1/jmeter,ham1/jmeter,etnetera/jmeter,etnetera/jmeter,benbenw/jmeter,benbenw/jmeter,ham1/jmeter,apache/jmeter,etnetera/jmeter,etnetera/jmeter,apache/jmeter,apache/jmeter,etnetera/jmeter,apache/jmeter,apache/jmeter,benbenw/jmeter,ham1/jmeter