message: Correctly override the abstract method in WindowsEnvTime::NowNanos().
diff: @@ -42,7 +42,7 @@ class WindowsEnvTime : public EnvTime {
  }
  }
  - uint64 NowNanos() {
  + uint64 NowNanos() const override {
  if (GetSystemTimePreciseAsFileTime_ != NULL) {
  // GetSystemTimePreciseAsFileTime function is only available in latest
  // versions of Windows, so we need to check for its existence here.
  