Fix AphrontCrumbView (phutil_tag)

Summary: Proper fix is to do some layout work in Diffusion. Short of that, make this escape properly.

Test Plan: Viewed various crumbs, no more overescaping for non-diffusion crumbs.

Reviewers: vrana

Reviewed By: vrana

CC: aran

Differential Revision: https://secure.phabricator.com/D4641