Smaller loading bar based on feedback
Smaller loading bar based on feedback

Summary:
This diff removes the hostname from the loading bar and shrinks it down so it's inside the margins of the safe area view, never blocking app content inside the safe area.

Changelog: [General] [iOS] Shrink loading bar down to not cover safe area.

Reviewed By: shergin

Differential Revision: D21339480

fbshipit-source-id: e8416af63b7e06bcc21c7b6277d5d01d61eb3f73

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