Unless NRT is doing the same sealed bag thing as EU airports for duty free, I don't think you'll be able to take it through security at YYZ. However, I'm pretty sure they don't, as all the signs only indicate they accept the anti-tamper bags from EU duty free.
Your only other real option is to check your rolley bag at YYZ, with your duty free inside. There are airline desks in the connecting luggage drop-off area, I would assume you can do it there.
Alas, this is a fact of life of the Global War on Fluids.