[testsfail] DemoPrivateProtobuf hang in CI

Also seen on an unrelated MP:

https://jenkins.qa.ubuntu.com/job/mir-utopic-amd64-ci/267/consoleText

Not been able to reproduce locally (yet). Could it be AMD64 specific?

Found a race condition in the exercised code (but not yet clear that causes this symptom).

And a third instance, also AMD64:

https://jenkins.qa.ubuntu.com/job/mir-utopic-amd64-ci/270/consoleText

(Which is after eliminating the race condition mentioned above.)

Fix committed into lp:mir at revision None, scheduled for release in mir, milestone 0.9.0

This bug was fixed in the package mir - 0.9.0+15.04.20141125-0ubuntu1

---------------
mir (0.9.0+15.04.20141125-0ubuntu1) vivid; urgency=medium

  [ Alberto Aguirre ]
  * New upstream release 0.9.0 (https://launchpad.net/mir/+milestone/0.9.0)
    - Enhancements:
      . New simpler API to configure and run a mir server.
      . The event loop is now based on GLib's main loop library instead of
        Boost.Asio.
      . For Android platforms, the server now sends buffer fence fds to its
        clients instead of potentially stalling the compositor thread waiting
        for them to be signalled.
      . New client debug interface to translate from surface to screen
        coordinates.
    - ABI summary: Servers need rebuilding, but clients do not;
      . Mirclient ABI unchanged at 8
      . Mircommon ABI bumped to 3
      . Mirplatform ABI bumped to 4
      . Mirserver ABI bumped to 27
    - Bug fixes:
      . Add a debug interface to translate from surface to screen coordinates
        (LP: #1346633)
      . Ensure a buffer requested by a surface is not delivered
        after the surface is deleted (LP: #1376324)
      . Overlays are not displayed onscreen in some positions (LP: #1378326)
      . Server aborts when an exception is thrown from the main thread
        (LP: #1378740)
      . Fix race causing lost alarm notifications (LP: #1381925)
      . Avoid lifecycle notifications racing with connection release
        (LP: #1386646)
      . Improve error checking and reporting for the client library
       (LP: #1390388)
      . Mir demo-shell now detects power button using proper Linux scan codes
       (LP: #1303817)
      . A prompt session with an invalid application pid should be an error
        (LP: #1377968)
      . When XDG_RUNTIME_DIR is defined but pointing to a non-existing
        directory use "/tmp" (LP: #1304873)
      . [regression] demo-shell bypass is not used on fullscreen surfaces if
        there are windowed surfaces behind (LP: #1378706)
      . Mir upgrade through dist-upgrade installs incorrect platform
        (LP: #1378995)
      . Fix Mir progressbar example using internal glibc defines(LP: #239272)
      . Stop the default_lifecycle_event_handler raising SIGHUP while
        disconnecting (LP: #1386185)
      . [regression] Mir fails to build with MIR_ENABLE_TESTS=OFF (LP: #1388539)
      . [regression] mir_demo_server_basic does not start (LP: #1391923)

  [ Ubuntu daily release ]
  * New rebuild forced
 -- Ubuntu daily release <email address hidden> Tue, 25 Nov 2014 17:49:24 +0000