Put the execution of the java8 extension into a profile, so that Travis can test it in java7 and java8 vms without breaking. In pre-1.8 vms the java8 extension will simply be ignored.
Put the execution of the java8 extension into a profile, so that Travis can test it in java7 and java8 vms without breaking. In pre-1.8 vms the java8 extension will simply be ignored.

This doesn't change -source/-target settings on any module, so if this is built on a java8 vm, it should produce code appropriate to 1.6 for core, and 1.8 for the java8 module.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=132510396

google/truth,cgruber/truth,cgruber/truth,google/truth,google/truth