R1:7a8d489ebdbd

Fix a HunkParser typo, "identcal" -> "identical"

Summary: See rP3f8eccdaec8f85933bfea6ce5348bde25ced0489.

Test Plan: Read carefully.

Reviewers: amckinley, avivey

Reviewed By: avivey

Subscribers: avivey

Differential Revision: https://secure.phabricator.com/D20499