Fixed one more minor compiler warning.
Fixed one more minor compiler warning.

AveRapina/visionworkbench,DougFirErickson/visionworkbench,DougFirErickson/visionworkbench,AveRapina/visionworkbench,fengzhyuan/visionworkbench,AveRapina/visionworkbench,fengzhyuan/visionworkbench,AveRapina/visionworkbench,AveRapina/visionworkbench,DougFirErickson/visionworkbench,fengzhyuan/visionworkbench,DougFirErickson/visionworkbench,fengzhyuan/visionworkbench,fengzhyuan/visionworkbench,DougFirErickson/visionworkbench,fengzhyuan/visionworkbench,AveRapina/visionworkbench,fengzhyuan/visionworkbench,DougFirErickson/visionworkbench