Provide an opt-out from clearing media items on stop

After removing the deprecated call to player.stop(/* reset= */ true) and instead using two calls to the player, overridding stop in a ForwardingPlayer does not help to avoid clearing the player. To remove the deprecation we need an option so that users who want not to clear the player have a way to do so.

PiperOrigin-RevId: 411518090

RELEASENOTES.md

@@ -14,6 +14,11 @@
 *   HLS:
     *   Support key-frame accurate seeking in HLS
         ([#2882](https://github.com/google/ExoPlayer/issues/2882)).
+    *   Correctly populate `Format.label` for audio only HLS streams
+        ([#9608](https://github.com/google/ExoPlayer/issues/9608)).
+*   MediaSession extension
+    *   Remove deprecated call to `onStop(/* reset= */ true)` and provide an
+        opt-out flag for apps that don't want to clear the playlist on stop.
 
 ### 2.16.1 (2021-11-18)
 

extensions/mediasession/src/main/java/com/google/android/exoplayer2/ext/mediasession/MediaSessionConnector.java

@@ -466,6 +466,7 @@ public final class MediaSessionConnector {
   private long enabledPlaybackActions;
   private boolean metadataDeduplicationEnabled;
   private boolean dispatchUnsupportedActionsEnabled;
+  private boolean clearMediaItemsOnStop;
 
   /**
    * Creates an instance.
@@ -486,6 +487,7 @@ public final class MediaSessionConnector {
     enabledPlaybackActions = DEFAULT_PLAYBACK_ACTIONS;
     mediaSession.setFlags(BASE_MEDIA_SESSION_FLAGS);
     mediaSession.setCallback(componentListener, new Handler(looper));
+    clearMediaItemsOnStop = true;
   }
 
   /**
@@ -700,6 +702,14 @@ public final class MediaSessionConnector {
   }
 
   /**
+   * Sets whether media items are cleared from the playlist when a client sends a {@link
+   * MediaControllerCompat.TransportControls#stop()} command.
+   */
+  public void setClearMediaItemsOnStop(boolean clearMediaItemsOnStop) {
+    this.clearMediaItemsOnStop = clearMediaItemsOnStop;
+  }
+
+  /**
    * Sets whether {@link MediaMetadataProvider#sameAs(MediaMetadataCompat, MediaMetadataCompat)}
    * should be consulted before calling {@link MediaSessionCompat#setMetadata(MediaMetadataCompat)}.
    *
@@ -1208,7 +1218,10 @@ public final class MediaSessionConnector {
     @Override
     public void onStop() {
       if (canDispatchPlaybackAction(PlaybackStateCompat.ACTION_STOP)) {
-        player.stop(/* reset= */ true);
+        player.stop();
+        if (clearMediaItemsOnStop) {
+          player.clearMediaItems();
+        }
       }
     }