Fix a bug where Phortune could fatal while building crumbs
Summary: Ref T12451. $this->getAccount() may not return an account.
Test Plan:
- Visit /phortune/X/, where X is the ID of an account you don't have permission to view.
- Before patch: fatal.
- After patch: normal policy exception page.
Reviewers: chad
Reviewed By: chad
Maniphest Tasks: T12451
Differential Revision: https://secure.phabricator.com/D17689