Remove native and web features from dioxus-html (#3006)

* remove native and web features from dioxus-html

* Fix downcasting web events

* Fix desktop with tokio disabled

packages/desktop/src/launch.rs

@@ -63,18 +63,20 @@ pub fn launch_virtual_dom_blocking(virtual_dom: VirtualDom, desktop_config: Conf
 /// Launches the WebView and runs the event loop, with configuration and root props.
 pub fn launch_virtual_dom(virtual_dom: VirtualDom, desktop_config: Config) -> ! {
     #[cfg(feature = "tokio_runtime")]
-    tokio::runtime::Builder::new_multi_thread()
-        .enable_all()
-        .build()
-        .unwrap()
-        .block_on(tokio::task::unconstrained(async move {
-            launch_virtual_dom_blocking(virtual_dom, desktop_config)
-        }));
+    {
+        tokio::runtime::Builder::new_multi_thread()
+            .enable_all()
+            .build()
+            .unwrap()
+            .block_on(tokio::task::unconstrained(async move {
+                launch_virtual_dom_blocking(virtual_dom, desktop_config)
+            }));
+
+        unreachable!("The desktop launch function will never exit")
+    }
 
     #[cfg(not(feature = "tokio_runtime"))]
     launch_virtual_dom_blocking(virtual_dom, desktop_config);
-
-    unreachable!("The desktop launch function will never exit")
 }
 
 /// Launches the WebView and runs the event loop, with configuration and root props.