Summary:Remove Trailing Spaces.
Why:
Sometimes there are conflicts with trailing spaces
Saves space
Those whose tools automatically delete them will have their pr watered down with trailing space removal
Closes https://github.com/facebook/react-native/pull/6787
Differential Revision: D3144704
fb-gh-sync-id: d8a62f115a3f8a8a49d5b07f56c540a02af38cf8
fbshipit-source-id: d8a62f115a3f8a8a49d5b07f56c540a02af38cf8