R1:8ff9d52a5941

Fix property list stacked UI

Summary: The stacked version of property lists is supposed to display like a normal definition list.

Test Plan: Test the stacked layout in Herald.

Reviewers: btrahan, epriestley

Reviewed By: epriestley

Subscribers: Korvin, epriestley

Differential Revision: https://secure.phabricator.com/D11014