[regression] Intermittent test failure BufferQueue/WithThreeOrMoreBuffers.queue_size_scales_with_client_performance

Status changed to 'Confirmed' because the bug affects multiple users.

That's from the 'earlier-release' branch that just landed. It only ever fails in CI but I thought I had solved it as CI started passing after my last attempt.

Fix committed to lp:mir revision r2868.

Fix committed into lp:mir at revision None, scheduled for release in mir, milestone 0.16.0

This bug was fixed in the package mir - 0.16.0+15.10.20150921.1-0ubuntu1

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mir (0.16.0+15.10.20150921.1-0ubuntu1) wily; urgency=medium

  [ Daniel van Vugt ]
  * New upstream release 0.16.0 (https://launchpad.net/mir/+milestone/0.16.0)
    - ABI summary: Only servers and graphics drivers need rebuilding;
      . Mirclient ABI unchanged at 9
      . Mirserver ABI bumped to 34
      . Mircommon ABI unchanged at 5
      . Mirplatform ABI bumped to 10
      . Mirprotobuf ABI bumped to 2
      . Mirplatformgraphics ABI bumped to 5
      . Mirclientplatform ABI unchanged at 3
    - Enhancements:
      . Significantly shortened buffer holding time for system compositors
        should yield higher/smoother frame rates.
      . Progress on new buffer semantics work.
      . Mir-on-x platform refinements, including support for guest platform,
        key combinations, rotation, display window size.
      . Enhanced cross-compilation, including multi-distro, and multi-arch
        support.
      . Added message auth code to make_event functions. Older implementations
        are now marked as deprecated.
      . Added EventBuilder for input platforms to use to construct events.
      . Improved logging.
      . Added protobuf versioning support.
      . Support for the NATIVE_WINDOW_CONSUMER_USAGE_BITS query.
      . Added utilities to detect the capabilities of an input device.
      . Initial refactoring to support renderers other than GL.
      . Optimized ANR logic to decide less frequent wakeups.
      . Allow clients to set their surface event handler up front.
      . Added ability to provide for setting a scale on BufferStream.
    - Bug fixes:
      . [regression] ubuntu-emulator fails to start Mir demos (LP: #1486535)
      . Overlayed framedropping clients freeze on mako (LP: #1391261)
      . [regression] Screen flickering and error messages on Android overlay
        surfaces: <ERROR> MirBufferStream: Error processing incoming buffer
        error registering graphics buffer for client use (LP: #1441553)
      . [silo0] exception thrown in cursor management code around monitor
        removals/additions (LP: #1483779)
      . mirclient.pc lists protobuf in Requires.private (LP: #1483876)
      . Overlays don't rotate when mga::DisplayBuffer is rotated (LP: #1485070)
      . cross-compile-chroot.sh fails on wily since the archive transition to
        GCC 5 (LP: #1486823)
      . [ FAILED ] ExchangeBufferTest.server_can_send_buffer
        (tests/integration-tests/test_exchange_buffer.cpp:441: Failure)
        (LP: #1487967)
      . Client fails to work with multiple client platform versions installed
        (LP: #1488500)
      . CI test failure in ClientLatency.triple_buffered_client_uses_all_buffers
        (LP: #1491876)
      . Intermittent CI failure in
        DisplayConfigurationTest.changing_focus_from_client_with_config_to_client_without_config_configures_display
        (LP: #1494663)
      . acceptance test ClientLatency.double_buffered_client_uses_all_buffers
        does not measure latency accurately (reports low latency when we know
        it's higher) (LP: #1447947)
      . make ptest returns 0 when tests f...