Summary:Explain the **motivation** for making this change. What existing problem does the pull request solve?
Fixes https://github.com/facebook/react-native/issues/6203
> SyntaxError: Use of const in strict mode.
- The rest of the file isn't using es6 anyway and babel-register is run on the file it's included in
**Test plan (required)**
Shouldn't have issues replacing it since it's used right after one time.
Closes https://github.com/facebook/react-native/pull/6329
Differential Revision: D3017697
Pulled By: martinbigio
fb-gh-sync-id: 42ee011d032a4bae3409b8e7793c9eb508719964
shipit-source-id: 42ee011d032a4bae3409b8e7793c9eb508719964
89a486eb3b