Merge "Switch away from std::async for proximity-active callback." into sc-dev am: c6ad94b6

}

void SensorService::notifyProximityStateLocked(

        const std::vector<sp<ProximityActiveListener>>& listnrs) {

    std::async(

        std::launch::async,

        [](uint64_t mySeq, bool isActive, std::vector<sp<ProximityActiveListener>> listeners) {

        const std::vector<sp<ProximityActiveListener>>& listeners) {

    const bool isActive = mProximityActiveCount > 0;

    const uint64_t mySeq = ++curProxCallbackSeq;

    std::thread t([isActive, mySeq, listenersCopy = listeners]() {

        while (completedCallbackSeq.load() != mySeq - 1)

            std::this_thread::sleep_for(1ms);

            for (auto& listener : listeners)

        for (auto& listener : listenersCopy)

            listener->onProximityActive(isActive);

        completedCallbackSeq++;

        },

        ++curProxCallbackSeq, mProximityActiveCount > 0,

        listnrs /* (this is meant to be a copy) */

    );

    });

    t.detach();

}

status_t SensorService::addProximityActiveListener(const sp<ProximityActiveListener>& callback) {