Fix web errors (#1040)

* Fix old `use` declarations

* Fix hidden lifetime parameter

* Fix missing methods in `web::Monitor`.

Originally fixed by @ryanisaacg in 94387c4bf5.

* Disable some tests and examples on `wasm32`

tests/send_objects.rs

@@ -1,6 +1,7 @@
 #[allow(dead_code)]
 fn needs_send<T: Send>() {}
 
+#[cfg(not(target_arch = "wasm32"))]
 #[test]
 fn event_loop_proxy_send() {
     #[allow(dead_code)]
@@ -10,6 +11,7 @@ fn event_loop_proxy_send() {
     }
 }
 
+#[cfg(not(target_arch = "wasm32"))]
 #[test]
 fn window_send() {
     // ensures that `winit::Window` implements `Send`