Jasmine Flowers is one of the most famous Chinese folk songs and dates back to the 18th century. It is often used these days to teach kids Chinese through song because of the simple lyrics and gentle pacing. It also features often in public Chinese performances.
The version we get on the night is actually Puccini's orchestral arrangement for the opera Turandot without any vocals. This is chosen to remind the audience that east has been meeting west for some time.