Only build, but don't run tests in MSRV CI (#2558)

* Only build, but don't run tests in MSRV CI

Since the MSRV of development dependencies can easily be bumped without it affecting the MSRV of the published version of `winit`

* Run clippy on stable Rust instead of MSRV Rust

clippy inspects the `rust-version` field, and only suggests changes that conform to that.

src/platform_impl/web/event_loop/runner.rs

@@ -15,6 +15,8 @@ use std::{
 
 pub struct Shared<T: 'static>(Rc<Execution<T>>);
 
+pub(super) type EventHandler<T> = dyn FnMut(Event<'_, T>, &mut ControlFlow);
+
 impl<T> Clone for Shared<T> {
     fn clone(&self) -> Self {
         Shared(self.0.clone())
@@ -54,11 +56,11 @@ impl<T: 'static> RunnerEnum<T> {
 
 struct Runner<T: 'static> {
     state: State,
-    event_handler: Box<dyn FnMut(Event<'_, T>, &mut ControlFlow)>,
+    event_handler: Box<EventHandler<T>>,
 }
 
 impl<T: 'static> Runner<T> {
-    pub fn new(event_handler: Box<dyn FnMut(Event<'_, T>, &mut ControlFlow)>) -> Self {
+    pub fn new(event_handler: Box<EventHandler<T>>) -> Self {
         Runner {
             state: State::Init,
             event_handler,
@@ -123,7 +125,7 @@ impl<T: 'static> Shared<T> {
     // Set the event callback to use for the event loop runner
     // This the event callback is a fairly thin layer over the user-provided callback that closes
     // over a RootEventLoopWindowTarget reference
-    pub fn set_listener(&self, event_handler: Box<dyn FnMut(Event<'_, T>, &mut ControlFlow)>) {
+    pub fn set_listener(&self, event_handler: Box<EventHandler<T>>) {
         {
             let mut runner = self.0.runner.borrow_mut();
             assert!(matches!(*runner, RunnerEnum::Pending));

src/platform_impl/web/event_loop/window_target.rs

@@ -14,7 +14,6 @@ use crate::event::{
     DeviceEvent, DeviceId as RootDeviceId, ElementState, Event, KeyboardInput, TouchPhase,
     WindowEvent,
 };
-use crate::event_loop::ControlFlow;
 use crate::window::{Theme, WindowId as RootWindowId};
 
 pub struct EventLoopWindowTarget<T: 'static> {
@@ -40,7 +39,7 @@ impl<T> EventLoopWindowTarget<T> {
         EventLoopProxy::new(self.runner.clone())
     }
 
-    pub fn run(&self, event_handler: Box<dyn FnMut(Event<'_, T>, &mut ControlFlow)>) {
+    pub fn run(&self, event_handler: Box<runner::EventHandler<T>>) {
         self.runner.set_listener(event_handler);
         let runner = self.runner.clone();
         self.runner.set_on_scale_change(move |arg| {

src/platform_impl/web/window.rs

@@ -249,7 +249,7 @@ impl Window {
         } else {
             self.canvas
                 .borrow()
-                .set_attribute("cursor", *self.previous_pointer.borrow());
+                .set_attribute("cursor", &self.previous_pointer.borrow());
         }
     }