Fix unused parameter warning in ROOT 7 TObjectDrawable
Fix unused parameter warning in ROOT 7 TObjectDrawable

See link below for example warning:
http://cdash.cern.ch/viewBuildError.php?type=1&buildid=425972

olifre/root,root-mirror/root,olifre/root,root-mirror/root,karies/root,karies/root,root-mirror/root,karies/root,root-mirror/root,root-mirror/root,olifre/root,karies/root,karies/root,olifre/root,olifre/root,olifre/root,root-mirror/root,karies/root,karies/root,root-mirror/root,olifre/root,karies/root,olifre/root,olifre/root,karies/root,root-mirror/root,root-mirror/root,karies/root,root-mirror/root,root-mirror/root,olifre/root,olifre/root,karies/root