Fix error creating repository from file:/// location, due to uninitialized variable.

Summary: This was broken in rP51fb1ca16d7f.

Test Plan: Imported a repository with file:/// location, it worked.

Reviewers: epriestley, Blessed Reviewers

Reviewed By: epriestley

CC: Korvin, epriestley, aran

Differential Revision: https://secure.phabricator.com/D7636