[gnome-boxes] machine: Disconnect signal for correct object

[Zeeshan Ali Khattak <zeeshanak src gnome org>]

commit 9d21e908a4aacb61617ba18c6759ab74005988f2
Author: Zeeshan Ali (Khattak) <zeeshanak gnome org>
Date:   Thu Sep 4 14:53:32 2014 +0100

    machine: Disconnect signal for correct object
    
    When we moved from listening to ui_state changes from App to AppWindow
    in commit 6463ad23, we forgot to update the disconnection part.

 src/machine.vala |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/src/machine.vala b/src/machine.vala
index a0593cc..47b7df9 100644
--- a/src/machine.vala
+++ b/src/machine.vala
@@ -504,7 +504,7 @@ private abstract class Boxes.Machine: Boxes.CollectionItem, Boxes.IPropertiesPro
 
         set_screenshot_enable (false);
         if (ui_state_id != 0) {
-            App.app.disconnect (ui_state_id);
+            window.disconnect (ui_state_id);
             ui_state_id = 0;
         }