Fix object code

scrollbar.go

@@ -172,14 +172,14 @@ func (this *Scrollbar) handleKeyDown (key input.Key, numpad bool) bool {
 
 	switch key {
 	case input.KeyUp, input.KeyLeft:
-		if modifiers.Alt {
+		if modifiers.Alt() {
 			this.SetValue(0)
 		} else {
 			this.scrollBy(this.StepSize())
 		}
 		return true
 	case input.KeyDown, input.KeyRight:
-		if modifiers.Alt {
+		if modifiers.Alt() {
 			this.SetValue(1)
 		} else {
 			this.scrollBy(-this.StepSize())
@@ -320,12 +320,13 @@ func (this *Scrollbar) newLinkCookie (subCookies ...event.Cookie) *scrollbarCook
 	}
 }
 
-func (this *scrollbarCookie) Close () {
+func (this *scrollbarCookie) Close () error {
 	for _, cookie := range this.subCookies {
 		cookie.Close()
 	}
 	this.owner.layout.linked = nil
 	this.owner.box.SetAttr(tomo.ALayout(this.owner.layout))
+	return nil
 }
 
 type scrollbarLayout struct {