Remove warnings when generating docs

Sphinx generates a warning about having too few underlines under the
title "ADD_ANGULAR_MODULES". The generated docs are still correct
(title is generated with an underline), so this change only needed
to eliminate the warning messages.

Change-Id: I18e4cdfcb97bcb08ede98f921de1f975d9a64cf5
Closes-Bug: #1329562
Merge "Remove warnings when generating docs"