Convert fb_xplat_cxx to Skylark
Convert fb_xplat_cxx to Skylark

Reviewed By: ttsugriy

Differential Revision: D6937683

fbshipit-source-id: 472c95b393d054c29413a46b86bf03559aff8741

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