R1:eb3fd2b7f513

Fix an issue with marking aborted buildables failed when more than one build is aborted

Summary: See <https://discourse.phabricator-community.org/t/upgrade-issue-2018-week-7-mid-february/1139>.

Test Plan: Used `bin/storage upgrade -f --apply ...` to re-apply the migration.

Differential Revision: https://secure.phabricator.com/D19116