An attempt by Ecuadorian villagers to have a Canadian court enforce a $19-billion judgment awarded in their country against…Chevron Corp. got off to a rocky start Thursday…Ontario Superior Court Justice David Brown…noted an Ontario court should not even think about weighing in unless there had been a final judgment in the South American country and no one had persuaded him there was one… The award to the villagers was made in Ecuador for black sludge contamination of a rainforest between 1972 and 1990 by Texaco, which Chevron Corp. bought in 2001. Chevron Corp. maintains it won't pay because it contends Texaco dealt with the problem before it was bought.