libvulkan: Check for negative in signed -> unsigned conversion

        return VK_ERROR_INITIALIZATION_FAILED;

    }

    uint32_t min_undequeued_buffers;

    err = surface.window->query(

        surface.window.get(), NATIVE_WINDOW_MIN_UNDEQUEUED_BUFFERS,

        reinterpret_cast<int*>(&min_undequeued_buffers));

    if (err != 0) {

    int query_value;

    err = surface.window->query(surface.window.get(),

                                NATIVE_WINDOW_MIN_UNDEQUEUED_BUFFERS,

                                &query_value);

    if (err != 0 || query_value < 0) {

        // TODO(jessehall): Improve error reporting. Can we enumerate possible

        // errors and translate them to valid Vulkan result codes?

        ALOGE("window->query failed: %s (%d)", strerror(-err), err);

        ALOGE("window->query failed: %s (%d) value=%d", strerror(-err), err,

              query_value);

        return VK_ERROR_INITIALIZATION_FAILED;

    }

    uint32_t min_undequeued_buffers = static_cast<uint32_t>(query_value);

    // The MIN_UNDEQUEUED_BUFFERS query doesn't know whether we'll be using

    // async mode or not, and assumes not. But in async mode, the BufferQueue

    // requires an extra undequeued buffer.