Merge "Camera: Remove thread that keeps HAL service alive for extra delay"

const std::string kLegacyProviderName("legacy/0");

const std::string kExternalProviderName("external/0");

const bool kEnableLazyHal(property_get_bool("ro.camera.enableLazyHal", false));

// The extra amount of time to hold a reference to an ICameraProvider after it is no longer needed.

// Hold the reference for this extra time so that if the camera is unreferenced and then referenced

// again quickly, we do not let the HAL exit and then need to immediately restart it. An example

// when this could happen is switching from a front-facing to a rear-facing camera. If the HAL were

// to exit during the camera switch, the camera could appear janky to the user.

const std::chrono::system_clock::duration kCameraKeepAliveDelay = 3s;

} // anonymous namespace

const float CameraProviderManager::kDepthARTolerance = .1f;

    std::lock_guard<std::mutex> lock(mProviderInterfaceMapLock);

    auto search = providerMap->find(cameraId.c_str());

    if (search != providerMap->end()) {

        auto ptr = search->second;

        auto future = std::async(std::launch::async, [ptr] {

            std::this_thread::sleep_for(kCameraKeepAliveDelay);

            IPCThreadState::self()->flushCommands();

        });

        // Drop the reference to this ICameraProvider. This is safe to do immediately (without an

        // added delay) because hwservicemanager guarantees to hold the reference for at least five

        // more seconds.  We depend on this behavior so that if the provider is unreferenced and

        // then referenced again quickly, we do not let the HAL exit and then need to immediately

        // restart it. An example when this could happen is switching from a front-facing to a

        // rear-facing camera. If the HAL were to exit during the camera switch, the camera could

        // appear janky to the user.

        providerMap->erase(cameraId.c_str());

        IPCThreadState::self()->flushCommands();

    } else {

        ALOGE("%s: Asked to remove reference for camera %s, but no reference to it was found. This "

                "could mean removeRef was called twice for the same camera ID.", __FUNCTION__,