Rescope disabled icon colors in phui-oi

Summary: This is a little too agressive, it's meant to only color direct icons, not icons inside tags if the object item is disabled.

Test Plan: Check closed tasks and see icon colors inside tags, check a disabled project, see disabled color.

Reviewers: epriestley

Reviewed By: epriestley

Subscribers: Korvin

Differential Revision: https://secure.phabricator.com/D18084