Fix path autocomplete
Summary: Paths autocompleter sometimes omits /.
Test Plan:
- Go to https://secure.phabricator.com/owners/new/.
- Write /specs/h to path.
- Delete the second slash resulting in /specsh.
- Don't find /specshistorytest.html in autocomplete.
Reviewers: epriestley
Reviewed By: epriestley
CC: aran, Korvin
Differential Revision: https://secure.phabricator.com/D2981