R1:12b225737100

Grid spacing for full Conpherence thread list

Summary: Moves to 4px grid / alignment.

Test Plan: Tested per photoshop gridlines, spacing measurements.

Reviewers: btrahan, epriestley

Reviewed By: epriestley

Subscribers: Korvin, epriestley

Differential Revision: https://secure.phabricator.com/D12197