PVS-Studio warning V547 for Chromium

IdleState CalculateIdleState(unsigned int idle_threshold) {
  ...
  DWORD current_idle_time = 0;
  ...
  // Will go -ve if we have been idle for
  // a long time (2gb seconds).
  if (current_idle_time < 0)
    current_idle_time = INT_MAX;
  ...
}

This suspicious code was found in Chromium project by PVS-Studio static code analyzer.
Warning message is:
V547 Expression 'current_idle_time < 0' is always false. Unsigned type value is never < 0.  browser  idle_win.cc  23

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