I tried to move them, but the tests fail then.  Moving them and importing from extra.QueueTest and extra.DequeTest compiles fine for java, but when I try to run an avian "make test" it complains:
test/ArrayDequeTest.java:6: package extra does not exist
import extra.DequeTest;
            ^
test/ArrayDequeTest.java:7: package extra does not exist
import extra.QueueTest;
            ^
test/LinkedBlockingQueueTest.java:5: package extra does not exist
import extra.QueueTest;

Thus I just added the small main function (as I am not sure how to get it to import from things from extra).

If you know the magic on how to do this, by all means, go ahead.