Only send last message if test still running (#939)
Only send last message if test still running (#939)

Fix the "Unknown test UID" message that appears in the web gui after any
test has completed. This is caused by the last test record containing
information about a test that has completed. Tests that complete are no
longer in the TEST_INSTANCES list, so the web gui can't retrieve any
more information about it.
google/openhtf,google/openhtf,google/openhtf,google/openhtf