Move X11 specific code in Window::setDesktops() to X11Window

src/window.cpp

@@ -1081,9 +1081,6 @@ void Window::setDesktops(QVector<VirtualDesktop *> desktops)
             }
         }
     }
-    if (info) {
-        info->setDesktop(desktop());
-    }
 
     if (isOnAllDesktops() != wasOnAllDesktops) {
         workspace()->updateOnAllDesktopsOfTransients(this);

src/x11window.cpp

@@ -1999,6 +1999,7 @@ void X11Window::doSetSkipSwitcher()
 
 void X11Window::doSetDesktop()
 {
+    info->setDesktop(desktop());
     updateVisibility();
 }