Track local freetype

Summary: Track local freetype for 2.4.12 upgrade with the new adobe hinting engine enabled by default.

Test Plan: merge me

Reviewers: randall.rushing, synergy

Reviewed By: synergy

Differential Revision: http://review.codefirex.com/D454

Change-Id: I208abef3076622fdba6f17c432746ff956465e56