2.x: Try fixing Travis CI lack of java (#5531)
2.x: Try fixing Travis CI lack of java (#5531)

* 2.x: Try fixing Travis CI lack of java

* Force dist: precise

* Oracle JDK 8 is then

ReactiveX/RxJava,NiteshKant/RxJava,ReactiveX/RxJava,NiteshKant/RxJava,akarnokd/RxJava,artem-zinnatullin/RxJava,artem-zinnatullin/RxJava,reactivex/rxjava,akarnokd/RxJava,reactivex/rxjava