Merge lp:~vanvugt/mir/fix-1669752 into lp:mir

[Daniel van Vugt]

Reintroduce manual compositor->stop()/start() calls that were removed
in r3996. Turns out we still need them to avoid mode changes initiated by
the server conflicting with redraws, which may crash (LP: #1669752).

[Mir CI Bot (mir-ci-bot)]

PASSED: Continuous integration, rev:4069
https://mir-jenkins.ubuntu.com/job/mir-ci/3100/
Executed test runs:
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-mir/4158
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-0-fetch/4245
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-1-sourcepkg/release=vivid+overlay/4235
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-1-sourcepkg/release=xenial+overlay/4235
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-1-sourcepkg/release=zesty/4235
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=amd64,compiler=clang,platform=mesa,release=zesty/4185
        deb: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=amd64,compiler=clang,platform=mesa,release=zesty/4185/artifact/output/*zip*/output.zip
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=amd64,compiler=gcc,platform=mesa,release=xenial+overlay/4185
        deb: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=amd64,compiler=gcc,platform=mesa,release=xenial+overlay/4185/artifact/output/*zip*/output.zip
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=amd64,compiler=gcc,platform=mesa,release=zesty/4185
        deb: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=amd64,compiler=gcc,platform=mesa,release=zesty/4185/artifact/output/*zip*/output.zip
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=cross-armhf,compiler=gcc,platform=android,release=vivid+overlay/4185
        deb: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=cross-armhf,compiler=gcc,platform=android,release=vivid+overlay/4185/artifact/output/*zip*/output.zip
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=i386,compiler=gcc,platform=android,release=vivid+overlay/4185
        deb: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=i386,compiler=gcc,platform=android,release=vivid+overlay/4185/artifact/output/*zip*/output.zip
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=i386,compiler=gcc,platform=mesa,release=xenial+overlay/4185
        deb: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=i386,compiler=gcc,platform=mesa,release=xenial+overlay/4185/artifact/output/*zip*/output.zip

Click here to trigger a rebuild:
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review: Approve (continuous-integration)

[Alan Griffiths (alan-griffiths)]

I would hope we can do better, but ok for now...

review: Approve

[Daniel van Vugt (vanvugt)]

I agree. We should be simply not crashing instead of working around it.

I only find this approach acceptable because it was already in place before.

=== modified file 'playground/demo-shell/window_manager.cpp'
--- playground/demo-shell/window_manager.cpp	2017-02-15 07:38:33 +0000
+++ playground/demo-shell/window_manager.cpp	2017-03-03 12:06:20 +0000
@@ -321,8 +321,10 @@
                                  mode_change) % nmodes;
                     }
                 });
-                                  
+
+            if (!rotating) compositor->stop();
             display->configure(*conf);
+            if (!rotating) compositor->start();
             force_redraw();
             return true;
         }