void RenderWidgetHostImpl::DecrementInFlightEventCount(
    InputEventAckSource ack_source) {
  --in_flight_event_count_;
  if (in_flight_event_count_ <= 0) {
    StopHangMonitorTimeout();
  } else {
    if (ack_source == InputEventAckSource::MAIN_THREAD)
      RestartHangMonitorTimeoutIfNecessary();
  }
}

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