1/3rd of China Proper(Tibet and Turkestan are not parts of China, not now and not then), including the capital and major coastal cities such as Tianjin, Shanghai, and Hong Kong.
No. The difference is that only the true history is taught in Korea no matter how painful it is, so that it will not be repeated in the future.
There is a good reason why Korea's flying high while Japan's sinking nowadays; Koreans try not to repeat their ancestor's mistakes 100 years ago, while Japan which teaches whitewashed history forgot what made their country great 100 years ago and is making a bunch of mistakes that's ruining Japan.
Now, which path does China want to go? By learning about the painful mistakes of the past in order not to repeat them, or whitewash history and repeat the past humiliations because Chinese people don't know and remember what got them into trouble 100 years ago?
It will be same as it is, except for the overthrow of communists in China and the independence of Tibet and Turkestan.