Unhighlight " No newline at end of file" in Differential

Summary:
It looks like there is really this text written e.g. at https://secure.phabricator.com/D1896#0a6a1957

I am not sure that it is the only place which needs to be fixed.

Test Plan: Display diff with no newline at end of file in Differential.

Reviewers: epriestley

Reviewed By: epriestley

CC: aran, epriestley

Differential Revision: https://secure.phabricator.com/D1900