Two months ago at the London Book Fair, where China was this year’s “guest of honor,” Ma Jian, the exiled author of the Tiananmen-era novel “Beijing Coma,” inked a red X across his face in an emotional protest against Chinese censorship. It may be a sign of the times that while drawing attention from the Western press, the move went almost unnoticed by other Chinese authors present, many of whom still live in China and find ways to circumvent the authorities.