Fabric: Fixed crash in RCTSurfaceTouchHandler (`unordered_set::at()`)
Fabric: Fixed crash in RCTSurfaceTouchHandler (`unordered_set::at()`)

Summary:
It's not fully clear why it happens but sometimes UIKit cancels (calling some UIGersureRecognizer interface) some UITouch events that seem never previously started. That might be a bug in UIKit or in our local registry.
That happens extremely rarely but happens.
After this change, RCTSurfaceTouchHandler will ignore those touches in production but crash in debug mode (I hope we can find a repro case and fix it).

Anyway, ignoring canceling of touches that RCTSurfaceTouchHandler is not aware of should not be a big deal.

Changelog: [Internal] Fabric-specific internal change.

Reviewed By: mdvacca

Differential Revision: D19221204

fbshipit-source-id: 77ce773f7bcc31725bf90a182a91789fd5deeedb

janicduplessis/react-native,facebook/react-native,arthuralee/react-native,exponent/react-native,facebook/react-native,hoangpham95/react-native,javache/react-native,javache/react-native,myntra/react-native,hammerandchisel/react-native,exponentjs/react-native,janicduplessis/react-native,pandiaraj44/react-native,facebook/react-native,myntra/react-native,pandiaraj44/react-native,exponent/react-native,hoangpham95/react-native,facebook/react-native,hammerandchisel/react-native,facebook/react-native,hammerandchisel/react-native,pandiaraj44/react-native,facebook/react-native,exponent/react-native,myntra/react-native,facebook/react-native,myntra/react-native,exponentjs/react-native,hoangpham95/react-native,hoangpham95/react-native,javache/react-native,javache/react-native,arthuralee/react-native,hammerandchisel/react-native,exponentjs/react-native,hoangpham95/react-native,exponent/react-native,pandiaraj44/react-native,hammerandchisel/react-native,javache/react-native,javache/react-native,janicduplessis/react-native,pandiaraj44/react-native,exponent/react-native,pandiaraj44/react-native,janicduplessis/react-native,javache/react-native,exponentjs/react-native,javache/react-native,hoangpham95/react-native,exponent/react-native,facebook/react-native,exponentjs/react-native,arthuralee/react-native,exponentjs/react-native,myntra/react-native,hoangpham95/react-native,javache/react-native,pandiaraj44/react-native,myntra/react-native,hammerandchisel/react-native,exponentjs/react-native,hammerandchisel/react-native,myntra/react-native,exponent/react-native,janicduplessis/react-native,exponentjs/react-native,janicduplessis/react-native,hoangpham95/react-native,facebook/react-native,arthuralee/react-native,janicduplessis/react-native,janicduplessis/react-native,myntra/react-native,arthuralee/react-native,exponent/react-native,pandiaraj44/react-native,myntra/react-native,hammerandchisel/react-native