message: Fix a C++ exception on unit relocation
diff: @@ -1835,6 +1835,9 @@ class RFCUtils:
  lCoreCities = self.getCoreCityList(iPlayer, self.getReborn(iPlayer))
  dUnits = {}
  + if not lCoreCities:
  + self.killUnits(lUnits)
  +
  for unit in lUnits:
  iUnitType = unit.getUnitType()
  if iUnitType in dUnits:
  @@ -1847,6 +1850,7 @@ class RFCUtils:
  index = i % (len(lCoreCities) * 2)
  if index < len(lCoreCities):
  city = lCoreCities[index]
  + if unit.getX() >= 0 and unit.getY() >= 0:
  unit.setXY(city.getX(), city.getY(), False, True, False)
  def flipOrCreateDefenders(self, iNewOwner, lUnits, tPlot, iNumDefenders):
  