LibWeb: Update HTMLMediaElements' playback positions when invisible

Author: https://github.com/Zaggy1024
Commit: 16b296c090
Pull-request: https://github.com/LadybirdBrowser/ladybird/pull/6410
Reviewed-by: https://github.com/R-Goc
Reviewed-by: https://github.com/gmta ✅

Libraries/LibWeb/HTML/HTMLMediaElement.cpp

@@ -1159,8 +1159,6 @@ void HTMLMediaElement::set_selected_video_track(Badge<VideoTrack>, GC::Ptr<HTML:
 
 void HTMLMediaElement::update_video_frame_and_timeline()
 {
-    if (!paintable())
-        return;
     if (!m_playback_manager)
         return;
 
@@ -1181,7 +1179,7 @@ void HTMLMediaElement::update_video_frame_and_timeline()
         needs_display = true;
     }
 
-    if (needs_display)
+    if (needs_display && paintable())
         paintable()->set_needs_display();
 }