Adds comments and changes how the custom callback
"on_send_to_external" gets code attached.
Previous callback version is deprecated in future
versions of Rails. This was changed as part of
work on canvas_zendesk_plugin which is
a separate project.
Testing Plan:
---------------------
Nothing to test. No change in behavior.
Tests for "canvas_zendesk_plugin" cover this as well.
Change-Id: I21fd4e20985b4a79b19578611d05e32c3b4b564f
Reviewed-on: https://gerrit.instructure.com/11004
Tested-by: Jenkins <jenkins@instructure.com>
Reviewed-by: Cameron Matheson <cameron@instructure.com>
Mark Ericksen