Comment 2 for bug 1231902

The server process left running is an artefact of "--gtest_break_on_failure" which exit the test process before sending SIGTERM to the server.

There are two failure modes:

1. Attempting to write to std::cerr after the stream objects are destroyed.
2. Attempting to access boost::system::error_code::message and calling a pure virtual function.

Both look like the process is closing down without first joining any active threads. (I'm still looking for the root cause.)