edx/edx-platform — pull request #6295 by tymofij (2014-12-17 20:55:55+00:00)
Title: make block.get_parent() work.

Implemented by @jimabramson, this is just a cherry-pick
We need this in our feature branch to make building course structure faster

reviewed and merged in https://github.com/edx/edx-platform/pull/6175

cc @dmitchell @cahrens @cpennington @andy-armstrong