Auto merge of #11443 - kyleheadley:remove_trait_11339, r=asajeffrey

Remove CompositorEventListener trait

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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #11339 (github issue number if applicable).

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- [ ] There are tests for these changes OR
- [X] These changes do not require tests because refactoring

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ports/cef/browser.rs

@@ -27,8 +27,8 @@ thread_local!(pub static BROWSERS: RefCell<Vec<CefBrowser>> = RefCell::new(vec!(
 
 pub enum ServoBrowser {
     Invalid,
-    OnScreen(Browser),
-    OffScreen(Browser),
+    OnScreen(Browser<glutin_app::window::Window>),
+    OffScreen(Browser<window::Window>),
 }
 
 impl ServoBrowser {