Revert "Pin apache-harmony-tests to Java 1.7 / v52"
Commit 1ab6e78b23a8cc063c29e67a1d69f487baa1f0dc makes this unnecessary.
Bug: 27637680
This reverts commit 10cafe2a.
(cherry picked from 973cf9e2)
Change-Id: I259166ee2594fbb73bdfa67a389ec2b009bd8c43