Create closure type; allow async event handlers in props; allow short hand event handlers (#2437)

* create closure type; allow async event handlers in props; allow shorthand event handlers

* test forwarding event handlers with the shorthand syntax

* fix clippy

* fix imports in spawn async doctest

examples/weather_app.rs

@@ -25,7 +25,7 @@ fn app() -> Element {
                 div { class: "flex items-start justify-center flex-row",
                     SearchBox { country }
                     div { class: "flex flex-wrap w-full px-2",
-                        div { class: "bg-gray-900 text-white relative min-w-0 break-words rounded-lg overflow-hidden shadow-sm mb-4 w-full bg-white dark:bg-gray-600",
+                        div { class: "bg-gray-900 text-white relative min-w-0 break-words rounded-lg overflow-hidden shadow-sm mb-4 w-full dark:bg-gray-600",
                             div { class: "px-6 py-6 relative",
                                 if let Some(Ok(weather)) = current_weather.read().as_ref() {
                                     CountryData {
@@ -122,7 +122,7 @@ fn SearchBox(mut country: Signal<WeatherLocation>) -> Element {
                         placeholder: "Country name",
                         "type": "text",
                         autofocus: true,
-                        oninput: move |e| input.set(e.value())
+                        oninput: move |e: FormEvent| input.set(e.value())
                     }
                     svg {
                         class: "w-4 h-4 absolute left-2.5 top-3.5",