[core] Prefix stylesheet names to prevent collisions

[oliviertassinari]

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Users might want to use the withStyles Higher-order Component and use a stylesheet name conflicting with our internal ones. To prevent that issue, I have prefixed them to reduce the conflict probability.

[mbrookes]

I have prefixed them to reduce the conflict probability.

Won't the unique ID take care of that?

[oliviertassinari]

@mbrookes What unique ID are you referring to? The name is on a global namespace and user can inject styles with the same one. If they do, the injection order would no longer be correct.

[mbrookes]

@oliviertassinari I was talking about the number added to the generated className, but I hadn't thought about injection order.