Fix Incremental children flow type
Fix Incremental children flow type

Summary: Incremental appears to be causing flow errors on Github master causing CI to fail.

Reviewed By: RSNara

Differential Revision: D10205146

fbshipit-source-id: b86c2d099a2041ab1429b9aacb78ff1b382dca41

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