applets/systray: reset index history in hidden view

BUG: 459421
FIXED-IN: 5.26
(cherry picked from commit b45660f2)

applets/systemtray/package/contents/ui/ExpandedRepresentation.qml

@@ -203,6 +203,7 @@ Item {
             onVisibleChanged: {
                 if (visible) {
                     layout.forceActiveFocus();
+                    systemTrayState.oldVisualIndex = systemTrayState.newVisualIndex = -1;
                 }
             }
         }