It was possible for thread2 to run before thread1 in the fname
concurrency tests. When this happens the assertions in the fname
concurrency tests fail. In each fname test block until thread 1 signals
the test before creating thread 2. In the different fname test block
until thread 2 signals the test before beginning the actual test work.
This ensures everyone has started as expected before checking the
expected done values.
Part of blueprint grizzly-testtools
Change-Id: I119fb03423324c9db9847b97d9bb69e71fef2aad