This example is used to confirm that resizable maps with multiple
            Google layers work properly.  Click the checkboxes to add/remove
            layers from the maps.  Use the layer switcher to change the map's
            base layer.  You should be able to confirm the following:
            
                - Adding and removing layers doesn't raise any errors
                (regardless of how many times the same layer is added/removed).
- The Google "Powered By" link is always visible and clickable
                when a Google layer is displayed.
- The Google "Terms of Use" link is always visible and clickable
                when a Google layer is displayed.
- Resizing a map (by resizing the browser window) and then
                changing base layer works well.  That is, the center & scale are
                preserved and all tiles are well aligned.
- Setting the base layer to the "Dummy Layer" hides all other
                Google base layers, "Powered By" link, and "Terms of Use" link.