Add implem of Integer.numberOfLeadingZeros().
Add implem of Integer.numberOfLeadingZeros().

japgolly/scala-js,colinrgodsey/scala-js,sjrd/scala-js,mdedetrich/scala-js,spaced/scala-js,renyaoxiang/scala-js,doron123/scala-js,jmnarloch/scala-js,mdedetrich/scala-js,andreaTP/scala-js,colinrgodsey/scala-js,japgolly/scala-js,yawnt/scala-js,jasonchaffee/scala-js,nicolasstucki/scala-js,andreaTP/scala-js,scala-js/scala-js,Vp3n/scala-js,Vp3n/scala-js,CapeSepias/scala-js,renyaoxiang/scala-js,scala-js/scala-js,yawnt/scala-js,matthughes/scala-js,gzm0/scala-js,CapeSepias/scala-js,doron123/scala-js,lrytz/scala-js,SebsLittleHelpers/scala-js,mdedetrich/scala-js,renyaoxiang/scala-js,sjrd/scala-js,ummels/scala-js,spaced/scala-js,matthughes/scala-js,jmnarloch/scala-js,xuwei-k/scala-js,yawnt/scala-js,matthughes/scala-js,colinrgodsey/scala-js,gzm0/scala-js,scala-js/scala-js,jasonchaffee/scala-js,sjrd/scala-js,SebsLittleHelpers/scala-js,jmnarloch/scala-js,lrytz/scala-js,xuwei-k/scala-js,spaced/scala-js,doron123/scala-js,ummels/scala-js,nicolasstucki/scala-js,jasonchaffee/scala-js,ummels/scala-js,Vp3n/scala-js,andreaTP/scala-js,CapeSepias/scala-js,xuwei-k/scala-js,japgolly/scala-js