Fix makeCanvas() for IE after Retina feature introduced in 179d2e1
Fix makeCanvas() for IE after Retina feature introduced in 179d2e1

colinhunt/flot,cipix2000/engineering-flot,saike/flot,wet-boew/flot,mlitwiniuk/flot,soenter/flot,soenter/flot,Sensirion/flot,cipix2000/flot,ni-kismet/engineering-flot,chiu/flot,klarkc/flot,pepperdata/flot,andig/flot,flot/flot,chiu/flot,andig/flot,stanislavdavid/flot,mlitwiniuk/flot,magora-suchkov/flot,k-joseph/flot,resnick1223/flot,resnick1223/flot,chiu/flot,resnick1223/flot,lolifans/flot,mlitwiniuk/flot,wet-boew/flot,octavianCraciun/engineering-flot,k-joseph/flot,chaveiro/flot,saike/flot,chaveiro/flot,andig/flot,stanislavdavid/flot,k-joseph/flot,cipix2000/flot,MAMISHO/flot,Ninir/flot,matong/flot,stanislavdavid/flot,sedran/flot,petrvacha/flot,Ninir/flot,gdseller/flot,fashionsun/flot,chaveiro/flot,kongx73/flot,trask/flot,TrainingPeaks/flot,saike/flot,mcanthony/flot