Support shuffle mode in MediaSessionConnector.

Changes to the player's shuffle mode are forwarded to the media session.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=166057425

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

@@ -621,7 +621,9 @@ public final class MediaSessionConnector {
 
     @Override
     public void onShuffleModeEnabledChanged(boolean shuffleModeEnabled) {
-      // TODO: Support shuffle mode in MediaSessionConnector.
+      mediaSession.setShuffleMode(shuffleModeEnabled ? PlaybackStateCompat.SHUFFLE_MODE_ALL
+          : PlaybackStateCompat.SHUFFLE_MODE_NONE);
+      updateMediaSessionPlaybackState();
     }
 
     @Override
@@ -806,6 +808,14 @@ public final class MediaSessionConnector {
     }
 
     @Override
+    public void onSetShuffleMode(int shuffleMode) {
+      if (canDispatchToQueueNavigator(PlaybackStateCompat.ACTION_SET_SHUFFLE_MODE_ENABLED)) {
+        queueNavigator.onSetShuffleModeEnabled(player,
+            shuffleMode != PlaybackStateCompat.SHUFFLE_MODE_NONE);
+      }
+    }
+
+    @Override
     public void onAddQueueItem(MediaDescriptionCompat description) {
       if (queueEditor != null) {
         queueEditor.onAddQueueItem(player, description);

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

@@ -163,7 +163,7 @@ public abstract class TimelineQueueNavigator implements MediaSessionConnector.Qu
 
   @Override
   public void onSetShuffleModeEnabled(Player player, boolean enabled) {
-    // TODO: Implement this.
+    player.setShuffleModeEnabled(enabled);
   }
 
   private void publishFloatingQueueWindow(Player player) {