WindowClone: Don't consume button press events

There is no reason to do this.

Author: leolost2605

src/Widgets/MultitaskingView/WindowClone.vala

@@ -377,10 +377,6 @@ public class Gala.WindowClone : ActorTarget, RootTarget {
         window_title.allocate (window_title_alloc);
     }
 
-    public override bool button_press_event (Clutter.Event event) {
-        return Clutter.EVENT_STOP;
-    }
-
     private void update_hover_widgets (bool? animating = null) {
         if (animating != null) {
             in_slot_animation = animating;