usage of std:call_once in mirclient causes TLS collisions with some android devices

Looks like std::call_once is not really required. A static variable initialization has thread safety guarantees under c++11.

Fix committed into lp:mir at revision None, scheduled for release in mir, milestone 0.25.0

This bug was fixed in the package mir - 0.24.0+16.10.20160815.3-0ubuntu1

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mir (0.24.0+16.10.20160815.3-0ubuntu1) yakkety; urgency=medium

  * New upstream release 0.24.0 (https://launchpad.net/mir/+milestone/0.24.0)
    - ABI summary:
      . mirclient ABI unchanged at 9
      . mirserver ABI bumped to 41
      . mircommon ABI unchanged at 6
      . mirplatform ABI bumped to 12
      . mirprotobuf ABI unchanged at 3
      . mirplatformgraphics ABI bumped to 10
      . mirclientplatform ABI unchanged at 5
      . mirinputplatform ABI unchanged at 5
    - Enhancements:
      . Added a new tool 'mirvanity' which can use a high speed video camera
        to measure client-to-screen latency.
      . Added (build-time) support for desktop full OpenGL servers (disabled
        by default in favor of GLESv2).
      . Introduced new buffer semantics (NBS) and enabled it by default.
      . Avoided using libmirserver in mir_demo_standalone_render_overlays,
        making bringup traces less cluttered.
      . Removed TilingWindowManager from example servers.
      . Added two new mir_*_performance_test tools that are run as part of
        'mir_performance_tests'.
      . Added pointer confinement to the client API.
      . Added new platform supporting software EGLStreams.
      . Added an input platform that the nested server can use.
      . Allow configuration of the application_not_responding_detector
      . Handle server-side keymapping using XKBMapper.
      . Remove the offscreen display.
      . Add callback option to notify shells that the server is about to stop.
      . Add logging for ANativeWindow events on Android.
    - Bugs fixed:
      . usage of std:call_once in mirclient causes TLS collisions with some
        android devices (LP: #1599867)
      . AltGr not working on external keyboards (LP: #1565236)
      . [regression] unity8 fails to start when built with 0.24 series (lp:mir)
        (LP: #1597717)
      . CI failure in MirSurfaceVisibilityEvent.exposed_received_when_surface_
        raised_over_occluding_surface [called twice - over-saturated and active]
        (LP: #1556045)
      . package-built mir_demo_server does not start on device (LP: #1577357)
      . During surface creation, first stream in spec becomes default stream.
        (LP: #1577967)
      . mouse is getting stuck on a phantom edge (LP: #1580774)
      . [testsfail] in MirSurfaceVisibilityEvent.exposed_received_when_surface_
        raised_over_occluding_surface [never called] (LP: #1581385)
      . [enhancement] Add support for full OpenGL compositing (LP: #1420581)
      . [testsfail] ServerSignal.terminate_handler_is_called_for_SIGINT|SIGTERM
        (LP: #1570353)
      . [testsfail] ClientLatency.triple_buffered_client_has_less_than_two_
        frames_latency (LP: #1576690)
      . [testsfail] NestedServer.when_monitor_plugged_in_client_is_notified_of_
        new_display_configuration (LP: #1576760)
      . mir server crashed in what(): drmModeMoveCursor failed (returned -13)
        (LP: #1579630)
      . mirtest-dev is hard to use as the objects used are compiled with LTO
        (LP: #1583536)
      . [testsfail] ClientLogging.repo...