Show an info view warning for ongoing or failed builds in Differential
Summary:
Fixes T10136. This reinforces ongoing or failed builds in the comment action area.
We already emit a similar message for unit test failures from arc unit. This should probably obsolete that, eventually.
Test Plan:
Reviewers: chad
Reviewed By: chad
Maniphest Tasks: T10136
Differential Revision: https://secure.phabricator.com/D17140