For instance, this is useful for the jquery-ui-rails gem, which does not
use jQuery UI's own minification, but relies on Rails to minify the
files where necessary. Rails in turn uses UglifyJS for JS and YUI for
CSS, both of which respect the /*! ... */ convention.
(cherry picked from commit 37dcc3e21d, dropped menu, spinner and tooltip)
When using buttons in a .ui-widget-header, they were loosing their
styling on link elements. By scoping the selector just like is
done for .ui-widget-content, it fixes this problem
