Auto merge of #22730 - aditj:patch-2, r=ferjm

Changed return value of GetActiveCues

Return an empty TextTrackCueList rather than Some inside the GetActiveCues.

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components/script/dom/texttrack.rs

@@ -114,7 +114,7 @@ impl TextTrackMethods for TextTrack {
     fn GetActiveCues(&self) -> Option<DomRoot<TextTrackCueList>> {
         // XXX implement active cues logic
         //      https://github.com/servo/servo/issues/22314
-        None
+        Some(TextTrackCueList::new(&self.global().as_window(), &[]))
     }
 
     // https://html.spec.whatwg.org/multipage/#dom-texttrack-addcue