Auto merge of #25914 - paulrouget:lessRAF, r=jdm

Stop embedder calls and fake rAF when window not visible

This addresses 2 issues:

- a rAF loop might still be ongoing when the window is invisible if script decided that the rAF were going too fast (spurious rAF)
- a hidden window does not run the rAF loop, but the embedder would still be in animating mode

---
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- [ ] These changes fix #___ (GitHub issue number if applicable)

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components/compositing/compositor.rs

@@ -483,9 +483,7 @@ impl<Window: WindowMethods + ?Sized> IOCompositor<Window> {
                 ShutdownState::NotShuttingDown,
             ) => {
                 self.pipeline_details(pipeline_id).visible = visible;
-                if visible {
-                    self.process_animations();
-                }
+                self.process_animations();
             },
 
             (Msg::PipelineExited(pipeline_id, sender), _) => {