Properly stop PlayerService

This commit is a consequence of the commit "Drop some assumptions on how PlayerService is started and reused". Since the assumptions on how the PlayerService is started and reused have changed, we also need to adapt the way it is stopped. This means allowing the service to remain alive even after the player is destroyed, in case the system is still accessing PlayerService e.g. through the media browser interface. The foreground service needs to be stopped and the notification removed in any case.

app/src/main/java/org/schabi/newpipe/player/ui/PopupPlayerUi.java

@@ -382,7 +382,7 @@ public final class PopupPlayerUi extends VideoPlayerUi {
                     private void end() {
                         windowManager.removeView(closeOverlayBinding.getRoot());
                         closeOverlayBinding = null;
-                        player.getService().stopService();
+                        player.getService().destroyPlayerAndStopService();
                     }
                 }).start();
     }