The control panel portlet copies its own theme and widgetset to a shared directory on the portal and then uses them to make sure it is fully independent of any versions of Vaadin installed on the portal etc. This works at least on Tomcat, but for some reason does not on your GlassFish - either because of the copying failing in general on GlassFish (wrong target directory?) or because of permission problems.
In your screenshot, it is quite obvious also other parts of the theme are missing.