Update .travis.yml

Change-Id: I3a19b35e26e8573685dfaf25e37bbef73d244322
diff --git a/.travis.yml b/.travis.yml
index 505db7d..8bf0bc7 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,8 +1,6 @@
 language: java
+dist: xenial
 jdk:
-  - oraclejdk8
-  - oraclejdk9
-  - oraclejdk10
   - openjdk8
-  - openjdk10
   - openjdk11
+  - openjdk12