mir should not composite/display buffers when an android driver calls ANativeWindow::cancelBuffer

This is possibly the root cause of the blank frame issue worked around by https://bazaar.launchpad.net/~unity-system-compositor-team/unity-system-compositor/trunk/view/head:/src/surface_coordinator.cpp#L58 .

TODO: check if we can remove that workaround if this bug is fixed.

@Alexandros,

Yes this is the root cause. We can remove that workaround once the fix for this bug lands on trunk.

Fix committed into lp:mir/devel at revision None, scheduled for release in mir, milestone Unknown

Fix committed to lp:mir/0.7 at revision 1877, scheduled for release in Mir 0.7.0

This bug was fixed in the package mir - 0.7.0+14.10.20140829-0ubuntu1

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mir (0.7.0+14.10.20140829-0ubuntu1) utopic; urgency=medium

  [ Daniel van Vugt ]
  * New upstream release 0.7.0 (https://launchpad.net/mir/+milestone/0.7.0)
    - Enhancements:
      . Test suite: Reworked mechanism to override Mir client functions
      . Demo shell: Detect custom rendering (decorations) to make it
        compatible with overlay optimizations
      . Make sure to preserve fd resources until the end of the sending
        of the message
      . Add test cases and script for tracking changes to the new ABIs:
        libmircommon, libmirplatform
      . Symbols file for libmirplatform
      . Symbols file for libmircommon
      . Symbols file for libmirserver
      . Various improvements to the SessionMediator test
      . Various build related improvements
      . Print testcase output during package build
      . Abort test when InProcessServer startup fails
      . Link the integration and unit tests against the server objects
      . Add a document detailing the useful tests to run and the useful
        logs to collect when troubleshooting a new android chipset
      . Enable motion event resampling and prediction for a more responsive
        touch experience.
    - ABI summary: Servers need rebuilding, but clients do not
      . Mirclient ABI unchanged at 8
      . Mircommon ABI bumped to 1
      . Mirplatform ABI bumped to 2
      . Mirserver ABI bumped to 25
    - API changes
      . Deleted function - frontend::Shell::create_surface_for(). If you have
        the std::shared_ptr<frontend::Session> session, you can just do
        session->create_surface(params) instead to get a SurfaceId
    - Bug fixes:
      . Ensure we process lifecycle events before the nested server is torn
        down (LP: #1353465)
      . Fix race in InputTestingServerConfiguration (LP: #1354446)
      . Fix fd leaks in prompt session frontend code and tests (LP: #1353461)
      . Detect the additional things the demo shell draws on the renderable
        list and avoid calling the optimized post function if they are being
        drawn (LP: #1348330)
      . Client: Fix SIGTERM dispatch in our default lifecycle event handler
        (LP: #1353867)
      . DemoRenderer: Don't try to create a texture of width zero.
        (LP: #1358210)
      . Fix CI failures (LP: #1358698)
      . Fix build failure: "variable ‘rc’ set but not used" which happens in
        release mode when NDEBUG is set (LP: #1358625)
      . Only enumerate exposed input surfaces to avoid delivering events to
        occluded surfaces (LP: #1359264)
      . Android: do not post driver cancelled buffers (LP: #1359406)
      . Client: Ensure our platform library stays loaded for as long as it is
        needed by other objects (LP: #1358191)
      . Examples: Register the DemoCompositor with the Scene to properly
        process visibility events (LP: #1359487)
      . Mir_demo_client_basic: Don't assert on user errors like failing to
        connect to a Mir server (LP: #1331958)
      . Tests: Explicitly depend on GMock target to avoid build races
        (LP: #1362646)

  [ Ubuntu dai...