Use double for YGRoundValueToPixelGrid calculations
Use double for YGRoundValueToPixelGrid calculations

Summary:
Use double for YGRoundValueToPixelGrid calculations as we were losing some precision in float operations

#Changelog:
[Internal][Yoga] Use double for YGRoundValueToPixelGrid calculations

Reviewed By: astreet

Differential Revision: D18225999

fbshipit-source-id: 69c05f56a0e0f3433bf0bd958aa07d26dd83fe02

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