Add flags needed to switch Jack to 1.8 for CTS targets

When linking against .jack files that contain 1.8 language
features Jack (currently) requires -D jack.java.source.version=1.8.

"core-tests" includes 1.8 language features.

core-tests-hostdex does not appear to be used in this
branch but it is used in downstream branches.

Bug: 27113322
Bug: 26953739
(cherry-picked from commit 6917cb59b4776bfd190e3ea26fd75156c6d9bd1e)

Change-Id: Id70a78aad45d15bdd23537df438fbfcd126f38d3
1 file changed