Frederic Massart authored Sep 22, 2016 and Dan Poltawski committed Sep 23, 2016

Progress bar styling has been removed as they do not appear to
be used anywhere, though MDL-56095 has been created to style them
as (with or without the styles) they remain unstyled.

The file responsive.scss has been removed, it was not used.

Part of MDL-55071