Why scrollTimeout is state?

[jongmoon]

First of all, I want to thank you for your great job.

I've checked performance for this component using Perf and I found needless render call.

Last tables means wasted time.

And It is caused by scrollTimeout is managed as a state. So I change this value as a Infinite's property.. this.scrollTimeout (from this.state.scrollTimeout).

As a result of above. I can remove needless render call. and I didn't recognize any abnormality after modifying.

But I wonder why scrollTimeout is managed as state instead of normal (private) variable. Thank you in advance.