Patch to test for entity_type

If you don't test for a non-null entity_type or id, you can get into fatal php errors downstream. Preventing cron from running and breaking ajax on the site. Even php warnings can break ajax. This was a really, really nasty bug that was hard to track down.

You'll get errors like ...
Error: Class name must be a valid object or a string in ... common.inc

or

Undefined index errors in common.inc

where it can't figure out the entity_type. This patch makes sure we only try to load valid entities that have ids and types. I've also re-formatted the code in this file to match drupal indenting standards. This module will break your views without this patch.