R1:ef43a9844023

Reload commits before publishing mail about them

This fixes this, which only crops up some of the time:

```
Daemon 39827 STDE [Thu, 04 Jun 2015 03:03:11 +0000] [2015-06-04 03:03:10] EXCEPTION: (PhutilProxyException) Error while executing Task ID 902271. {>} (PhabricatorDataNotAttachedException) Attempting to access attached data on PhabricatorRepositoryCommit (via getCommitData()), but the data is not actually attached. Before accessing attachable data on an object, you must load and attach it.
Daemon…