Video time never saved when playing in background

Description

When a video is played in background (Settings > Video 'Background/PiP mode': Play videos in background), we never call PlaylistManager.saveMediaMeta() so the progress is lost.

OP: https://forum.videolan.org/viewtopic.php?f=35&t=159135

Expected behavior

The progress is saved

Steps to reproduce

1. Enable Settings > Video 'Background/PiP mode': Play videos in background
2. Play a video
3. Turn the screen off
4. Switch to npause
5. Slide the notification
6. Return to the app: the progress is not saved

Screenshot / video

Context

App version

3.4.3

Android version

Device model

App mode

Smartphone