I been to three dealers to fix this problem.
As I posted before, the first dealer (Ourisman Chantilly Toyota) told me it is not under warranty because it is caused by some sort of chemical.
Manager at the second dealer (Ourisman Fairfax Toyota) told me he have never seen something like that and claims that coat may have been protective coat applied by the dealer that sold me the car and it is not part of the vehicle. So, he cannot give warranty service because if he give me the warranty and it turns out it was not part of vehicle, he might get fired. (He should be fired anyway for not knowing the vehicle at all!)
So I went to the dealer I bought the car. (which takes about 30~40 min drive from where I live

Koons Tysons Toyota )
It turns out they were the most friendly dealer. Manager looked at the armrest and told me it might have been some sold of cleanler that caused problem. (Which I didn't use!) But its still under warranty. He said he knows someone that does interior repair and he will have him repair that part instead of replacing whole thing because the color might not match with other parts if replaced. (True, but he may be lying to reduce cost. )
He wasn't able to contact that repair guy and he is supposed to call me to set an appoinment when he gets the call back from repair guy.
Hope this dealer doesn't turn me down too.
At least the manager did say it is covered by warranty.
PXLpainter//
Here is the picture of my armrest.
