Splice method on ext.headerFilters not working to IE <= 8

[viko21]

On the function attached to the click event for the OK button of the filters there is a splice method applied to the workingFilters variable. The slice method only receives one argument and this not work as expected on IE 8 and older versions, the method needs to receive a second argument to work fine. I removed the splice method to the workingFilters array in my code but I need to know what this splice do exactly with the workingFilters array.