Use phid instead of guid for image diff

Summary:
in https://secure.phabricator.com/rARC36de84ee, we changed to
use 'binary-phid' from 'binary-guid'. Several places are still using
'binary-guid'. Fix them.

Test Plan:
run 'arc patch' against a revision which was throwing
exception because of this issue and it worked.

Reviewed By: epriestley
Reviewers: epriestley, sgrimm
CC: aran, epriestley
Differential Revision: 624