emberjs/data — pull request #1208 by daliwali (2013-09-04 04:19:17+00:00)
Title: check if record exists for asynchronous belongsTo

This fixes a bug when an asynchronous 'belongsTo' relation is defined but does not exist. Before, it would call the `store.fetchRecord` method with an `undefined` 'record' argument, causing an error.