camptocamp/cgxp — pull request #407 by asaunier (2013-03-01 10:17:18+00:00)
Title: Make sure requested basemap exists before activating it

If a user loads a permalink with an invalid ``baselayer_ref`` parameter, the MapOpacitySlider widget fails and no basemap is displayed. This PR checks that the requested basemap is valid before trying to load it.