Playback view not updated after end of playback

[bernardorufino]

Play some music, a few seconds from the end background the app, make sure the song has ended (by looking at the clock!), go back to the app, playback controls (graph, current/total time displays and seek bar) remain in the state before the app was backgrounded. They should update themselves to paused mode (i.e. graph/seek bar empty and current/total time display = 0).