edx/edx-platform — pull request #3277 by olmar (2014-04-09 08:39:06+00:00)
Title: Do not allow user overwrite some parameters using custom parameters field. BLD-989.

Do not allow user to overwrite some LTI parameters(e.g. roles) via custom parameters field.

Issue: https://edx-wiki.atlassian.net/browse/BLD-989