On narrow dashboard columns, don't show col2 of obj-item

Summary: Hides the second column of info on narrow (33%) columns on dashboards on object-items.

Test Plan:
Tested a narrow left and narrow right column, 160px is gained back.

Reviewers: btrahan, epriestley

Reviewed By: epriestley

Subscribers: Korvin, epriestley

Differential Revision: https://secure.phabricator.com/D10962