Fix layoutSubviews error
Fix layoutSubviews error

namanhams/NMRangeSlider,jiamaozheng/NMRangeSlider,jfradj/NMRangeSlider,muZZkat/NMRangeSlider,ivasic/NMRangeSlider,Sega-Zero/NMRangeSlider,neonaldo/NMRangeSlider,mvelikov/NMRangeSlider