Steps to reproduce:
* Go to https://secure.phabricator.com/diffusion/P/browse/master/README
* Click Enable Blame
* Click the « to skip past a commit
Returns the following error:
```lang=none
>>> UNRECOVERABLE FATAL ERROR <<<
Call to a member function getCommitIdentifier() on a non-object
/core/lib/phabricator/src/applications/diffusion/controller/DiffusionBrowseFileController.php:894
┻━┻ ︵ ¯\_(ツ)_/¯ ︵ ┻━┻
```