Use alternative fill color when line color of TGeoVolume is black
Use alternative fill color when line color of TGeoVolume is black

Signed-off-by: Sergey Linev <e975f594b5fd242373e09af42cc211e3844763a6@gsi.de>

linev/jsroot,root-project/jsroot,root-project/jsroot,linev/jsroot,bellenot/jsroot,bellenot/jsroot,bellenot/jsroot