Move ControlFlow to EventLoopWindowTarget

Fixes #3042.

examples/drag_window.rs

@@ -21,12 +21,12 @@ fn main() -> Result<(), impl std::error::Error> {
     let mut switched = false;
     let mut entered_id = window_2.id();
 
-    event_loop.run(move |event, _, control_flow| match event {
+    event_loop.run(move |event, elwt| match event {
         Event::NewEvents(StartCause::Init) => {
             eprintln!("Switch which window is to be dragged by pressing \"x\".")
         }
         Event::WindowEvent { event, window_id } => match event {
-            WindowEvent::CloseRequested => control_flow.set_exit(),
+            WindowEvent::CloseRequested => elwt.exit(),
             WindowEvent::MouseInput {
                 state: ElementState::Pressed,
                 button: MouseButton::Left,