review: Fix more hardcoded paths in gradle build

[David Hill]

Kevin, if you could review:

https://bugs.openjdk.java.net/browse/JDK-8162114
webrev: http://cr.openjdk.java.net/~ddhill/8162114 <http://cr.openjdk.java.net/%7Eddhill/8162114>

-- 
David Hill<David.Hill at Oracle.com>
Java Embedded Development

"A man's feet should be planted in his country, but his eyes should survey the world."
-- George Santayana (1863 - 1952)