Fix handling of unknown metrics in graphs.
Fix handling of unknown metrics in graphs.

Skrupellos/facette,githubert/facette,facette/facette,facette/facette,psytra/facette,iaean/facette,iaean/facette,yonglehou/facette,facette/facette,yonglehou/facette,hirocaster/facette,githubert/facette,vovkasm/facette,Skrupellos/facette,iaean/facette,hirocaster/facette,psytra/facette,psytra/facette,hirocaster/facette,githubert/facette,Skrupellos/facette,vovkasm/facette,facette/facette,vovkasm/facette,yonglehou/facette