LibGUI: Remove premature return in Window::handle_key_event

Userland/Libraries/LibGUI/Window.cpp

@@ -446,7 +446,6 @@ void Window::handle_key_event(KeyEvent& event)
 {
     if (!m_focused_widget && event.type() == Event::KeyDown && event.key() == Key_Tab && !event.ctrl() && !event.alt() && !event.super()) {
         focus_a_widget_if_possible(FocusSource::Keyboard);
-        return;
     }
 
     if (m_focused_widget)