Call OnDismiss() in wxMSW wxPopupTransientWindow on deactivation

The window should be notified about its dismissal, as it happens in the
result of the user action and not due to a call to Dismiss() from the
program itself.

src/msw/popupwin.cpp

@@ -195,7 +195,7 @@ void wxPopupTransientWindow::Dismiss()
 void wxPopupTransientWindow::DismissOnDeactivate()
 {
     // Hide the window automatically when it loses activation.
-    Dismiss();
+    DismissAndNotify();
 
     // Activation might have gone to a different window or maybe
     // even a different application, don't let our owner continue