static/ext/src/dom/Element_style.js
function(width) {
        var me = this,
            isNum = (typeof width == 'number');

        if (isNum && me.autoBoxAdjust && !me.isBorderBox()) {
            width -= (me.getBorderWidth("lr") + me.getPadding("lr"));
        }
        return (isNum && width < 0) ? 0 : width;
    }
function(width) {
        var me = this,
            isNum = (typeof width == 'number');

        if (isNum && me.autoBoxAdjust && !me.isBorderBox()) {
            width -= (me.getBorderWidth("lr") + me.getPadding("lr"));
        }
        return (isNum && width < 0) ? 0 : width;
    }
function ( width ) { var me = this , isNum = ( typeof width == 'number' ) ; if ( isNum && me . autoBoxAdjust && ! me . isBorderBox ( ) ) { width -= ( me . getBorderWidth ( "lr" ) + me . getPadding ( "lr" ) ) ; } return ( isNum && width < 0 ) ? 0 : width ; }
TODO: Look at this private  ==> used by Fx
TODO : Look at this private == > used by Fx