Add missing update on repeat toggle mode change

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=220461315

library/ui/src/main/java/com/google/android/exoplayer2/ui/PlayerControlView.java

@@ -536,6 +536,7 @@ public class PlayerControlView extends FrameLayout {
         controlDispatcher.dispatchSetRepeatMode(player, Player.REPEAT_MODE_ALL);
       }
     }
+    updateRepeatModeButton();
   }
 
   /** Returns whether the shuffle button is shown. */