Ability to add custom class to CRM_Core_Session::setStatus

setStatus always puts the following div with the last class dependent on the type of status
<div class="messages status no-popup">

You can style all status blocks at once, but it would be useful to be able to add a custom class to statuses in php or smarty so users/developers can have differently-styled notices/errors for specific things.

That way one can, for example, have a "no-popup error" or "no-popup notice", etc with different styling.