Martial-arts film star Jackie Chan’s planned visit to Vietnam for a charity has been cancelled following an online backlash related to Beijing’s expansive claims in the disputed South China Sea.The Hong Kong-born actor was set to visit Hanoi on 10 November to support Operation Smile, a charity that gives free surgery to children with facial disfigurements.But the plans were scrapped after thousands of angry Facebook users flooded the charity’s official page when his visit was announced last w