Report errors from CtsTestServer for improved debugging

Switch from using ExecutionService.submit() to Executor.execute()
because the Future was never being checked. Switched to using
a Runnable, because no value is returned. Added logging for
any exception generated.

Bug: 21874093
Change-Id: Ie820e648f1e21177bd27aeab32002d59108ad0d6
1 file changed