By withdrawing Chinese people and stopping some trading programs with Vietnam, the Chinese authority may think they are punishing Vietnam for having caused damages to Chinese properties in Vietnam.
The consequence of this punishment would be higher unemployment rate in Vietnam. With an increasing unemployment and high anti-Chinese sentiment, a Jasmine Revolution would happen in Vietnam.
This revolution would bring a new government, which would be more pro-Western and less pro-Chinese, and would be a democratic regime with multi party system. This democratic movement in Vietnam would eventually encourage a democratic revolution in China to overthrow the Chinese Communist Party.