2.x: See if sudo required results in consistent build times (#5457)

Author: akarnokd

.travis.yml

@@ -11,7 +11,7 @@ jdk:
 # prevent travis running gradle assemble; let the build script do it anyway
 install: true
 
-sudo: false
+sudo: required
 # as per http://blog.travis-ci.com/2014-12-17-faster-builds-with-container-based-infrastructure/
 
 # script for build and release via Travis to Bintray