China has been allergic to the word "invasion", perhaps because they don't want it thrown at them if they attack Taiwan. But China is not happy with Russia over this.
Current events in Ukraine seem like the perfect experiment to see if taking Taiwan is possible.
If it's really, really useful, I don't see how happy/unhappy would enter into it.
What does "actual ally" mean, according to experts? Was the USSR an actual ally of anyone in WWII? The US sent a zillion dollars worth of Jeeps and spam on the basis of shared interests, not true friendship.
"Actual ally" as in "they let Russia launch part of the invasion from their territory". Even more: Belarus is at least talking about sending their own troops as well.
China has been allergic to the word "invasion", perhaps because they don't want it thrown at them if they attack Taiwan. But China is not happy with Russia over this.