Comment 2 for bug 1619448

StacktraceTop:
 libinput_device_config_accel_is_available (device=0x3231) at libinput.c:3707
 libinput_device_config_accel_set_speed (device=0x3231, speed=0) at libinput.c:3719
 mir::input::evdev::LibInputDevice::apply_settings (this=0x7f6ef0096f20, settings=...) at ./src/platforms/evdev/libinput_device.cpp:396
 operator() () at /usr/include/c++/6/functional:2136
 mir::dispatch::ActionQueue::dispatch(unsigned int) (this=this@entry=0x55e8f0e20790, events=<optimized out>) at ./src/common/dispatch/action_queue.cpp:65