Auto merge of #25799 - paulrouget:hideWindow, r=Manishearth

Hide window

Stop animations when the window is hidden.

Tested with both Immersive Mode, and regular window being minimized.

---
<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `___` with appropriate data: -->
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix #25794 (GitHub issue number if applicable)

ports/libsimpleservo/api/src/lib.rs

@@ -487,6 +487,17 @@ impl ServoGlue {
         self.process_event(WindowEvent::MediaSessionAction(action))
     }
 
+    pub fn change_visibility(&mut self, visible: bool) -> Result<(), &'static str> {
+        info!("change_visibility");
+        if let Ok(id) = self.get_browser_id() {
+            let event = WindowEvent::ChangeBrowserVisibility(id, visible);
+            self.process_event(event)
+        } else {
+            // Ignore visibility change if no browser has been created yet.
+            Ok(())
+        }
+    }
+
     fn process_event(&mut self, event: WindowEvent) -> Result<(), &'static str> {
         self.events.push(event);
         if !self.batch_mode {

ports/libsimpleservo/capi/src/lib.rs

@@ -686,6 +686,14 @@ pub extern "C" fn media_session_action(action: CMediaSessionActionType) {
     });
 }
 
+#[no_mangle]
+pub extern "C" fn change_visibility(visible: bool) {
+    catch_any_panic(|| {
+        debug!("change_visibility");
+        call(|s| s.change_visibility(visible));
+    });
+}
+
 pub struct WakeupCallback(extern "C" fn());
 
 impl WakeupCallback {