Properly protect moderated content in Templating::getContent

The Templating::getContent method left open the possibility that if a
user was not allowed to see the content, but the replacement i18n
message was not available, the content would be displayed.

Change-Id: I33ea2ed47039eb6cd58fb65c3308dd652de1cf88
Merge "Properly protect moderated content in Templating::getContent"