Slightly reduce number of cfgs (#3071)

* Make Linux platforms less dependent on the root monitor handle

* Add various functions to the Wayland platform to reduce cfgs

* Don't use a cfg in listen_device_events

* Don't use a cfg in set_content_protected

* Fix instance of a target_os cfg

src/platform_impl/web/window.rs

@@ -379,6 +379,8 @@ impl Inner {
         })
     }
 
+    pub fn set_content_protected(&self, _protected: bool) {}
+
     #[inline]
     pub fn has_focus(&self) -> bool {
         self.has_focus.load(Ordering::Relaxed)