Merge "Fix deadlock when transitioning to vr flinger" into oc-mr1-dev

    if (useVrFlinger) {

        auto vrFlingerRequestDisplayCallback = [this] (bool requestDisplay) {

            // This callback is called from the vr flinger dispatch thread. We

            // need to call signalTransaction(), which requires holding

            // mStateLock when we're not on the main thread. Acquiring

            // mStateLock from the vr flinger dispatch thread might trigger a

            // deadlock in surface flinger (see b/66916578), so post a message

            // to be handled on the main thread instead.

            sp<LambdaMessage> message = new LambdaMessage([=]() {

                ALOGI("VR request display mode: requestDisplay=%d", requestDisplay);

                mVrFlingerRequestsDisplay = requestDisplay;

            ConditionalLock _l(mStateLock,

                    std::this_thread::get_id() != mMainThreadId);

                signalTransaction();

            });

            postMessageAsync(message);

        };

        mVrFlinger = dvr::VrFlinger::Create(mHwc->getComposer(),

                                            vrFlingerRequestDisplayCallback);