Add listener callback for shuffle mode changes.

The listener implementations do not do anything yet.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=166056933

demos/main/src/main/java/com/google/android/exoplayer2/demo/EventLogger.java

@@ -99,6 +99,11 @@ import java.util.Locale;
     Log.d(TAG, "repeatMode [" + getRepeatModeString(repeatMode) + "]");
   }
 
+  @Override
+  public void onShuffleModeEnabledChanged(boolean shuffleModeEnabled) {
+    Log.d(TAG, "shuffleModeEnabled [" + shuffleModeEnabled + "]");
+  }
+
   @Override
   public void onPositionDiscontinuity() {
     Log.d(TAG, "positionDiscontinuity");

demos/main/src/main/java/com/google/android/exoplayer2/demo/PlayerActivity.java

@@ -501,6 +501,11 @@ public class PlayerActivity extends Activity implements OnClickListener, EventLi
     // Do nothing.
   }
 
+  @Override
+  public void onShuffleModeEnabledChanged(boolean shuffleModeEnabled) {
+    // Do nothing.
+  }
+
   @Override
   public void onPositionDiscontinuity() {
     if (inErrorState) {

extensions/flac/src/androidTest/java/com/google/android/exoplayer2/ext/flac/FlacPlaybackTest.java

@@ -132,6 +132,11 @@ public class FlacPlaybackTest extends InstrumentationTestCase {
       // Do nothing.
     }
 
+    @Override
+    public void onShuffleModeEnabledChanged(boolean shuffleModeEnabled) {
+      // Do nothing.
+    }
+
     private void releasePlayerAndQuitLooper() {
       player.release();
       Looper.myLooper().quit();

extensions/ima/src/main/java/com/google/android/exoplayer2/ext/ima/ImaAdsLoader.java

@@ -566,6 +566,11 @@ public final class ImaAdsLoader implements Player.EventListener, VideoAdPlayer,
     // Do nothing.
   }
 
+  @Override
+  public void onShuffleModeEnabledChanged(boolean shuffleModeEnabled) {
+    // Do nothing.
+  }
+
   @Override
   public void onPlayerError(ExoPlaybackException error) {
     if (playingAd) {

extensions/leanback/src/main/java/com/google/android/exoplayer2/ext/leanback/LeanbackPlayerAdapter.java

@@ -271,6 +271,11 @@ public final class LeanbackPlayerAdapter extends PlayerAdapter {
       // Do nothing.
     }
 
+    @Override
+    public void onShuffleModeEnabledChanged(boolean shuffleModeEnabled) {
+      // Do nothing.
+    }
+
     // SimpleExoplayerView.Callback implementation.
 
     @Override

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

@@ -619,6 +619,11 @@ public final class MediaSessionConnector {
       updateMediaSessionPlaybackState();
     }
 
+    @Override
+    public void onShuffleModeEnabledChanged(boolean shuffleModeEnabled) {
+      // TODO: Support shuffle mode in MediaSessionConnector.
+    }
+
     @Override
     public void onPlayerError(ExoPlaybackException error) {
       playbackException = error;

extensions/opus/src/androidTest/java/com/google/android/exoplayer2/ext/opus/OpusPlaybackTest.java

@@ -132,6 +132,11 @@ public class OpusPlaybackTest extends InstrumentationTestCase {
       // Do nothing.
     }
 
+    @Override
+    public void onShuffleModeEnabledChanged(boolean shuffleModeEnabled) {
+      // Do nothing.
+    }
+
     private void releasePlayerAndQuitLooper() {
       player.release();
       Looper.myLooper().quit();

extensions/vp9/src/androidTest/java/com/google/android/exoplayer2/ext/vp9/VpxPlaybackTest.java

@@ -164,6 +164,11 @@ public class VpxPlaybackTest extends InstrumentationTestCase {
       // Do nothing.
     }
 
+    @Override
+    public void onShuffleModeEnabledChanged(boolean shuffleModeEnabled) {
+      // Do nothing.
+    }
+
     private void releasePlayerAndQuitLooper() {
       player.release();
       Looper.myLooper().quit();

library/core/src/main/java/com/google/android/exoplayer2/ExoPlayerImpl.java

@@ -195,6 +195,9 @@ import java.util.concurrent.CopyOnWriteArraySet;
   public void setShuffleModeEnabled(boolean shuffleModeEnabled) {
     if (this.shuffleModeEnabled != shuffleModeEnabled) {
       this.shuffleModeEnabled = shuffleModeEnabled;
+      for (Player.EventListener listener : listeners) {
+        listener.onShuffleModeEnabledChanged(shuffleModeEnabled);
+      }
     }
   }
 
@@ -527,3 +530,4 @@ import java.util.concurrent.CopyOnWriteArraySet;
   }
 
 }
+

library/core/src/main/java/com/google/android/exoplayer2/Player.java

@@ -94,6 +94,13 @@ public interface Player {
      */
     void onRepeatModeChanged(@RepeatMode int repeatMode);
 
+    /**
+     * Called when the value of {@link #getShuffleModeEnabled()} changes.
+     *
+     * @param shuffleModeEnabled Whether shuffling of windows is enabled.
+     */
+    void onShuffleModeEnabledChanged(boolean shuffleModeEnabled);
+
     /**
      * Called when an error occurs. The playback state will transition to {@link #STATE_IDLE}
      * immediately after this method is called. The player instance can still be used, and

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

@@ -93,6 +93,11 @@ public final class DebugTextViewHelper implements Runnable, Player.EventListener
     // Do nothing.
   }
 
+  @Override
+  public void onShuffleModeEnabledChanged(boolean shuffleModeEnabled) {
+    // Do nothing.
+  }
+
   @Override
   public void onPositionDiscontinuity() {
     updateAndPost();

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

@@ -1079,6 +1079,11 @@ public class PlaybackControlView extends FrameLayout {
       updateNavigation();
     }
 
+    @Override
+    public void onShuffleModeEnabledChanged(boolean shuffleModeEnabled) {
+      // TODO: Update UI.
+    }
+
     @Override
     public void onPositionDiscontinuity() {
       updateNavigation();

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

@@ -896,6 +896,11 @@ public final class SimpleExoPlayerView extends FrameLayout {
       // Do nothing.
     }
 
+    @Override
+    public void onShuffleModeEnabledChanged(boolean shuffleModeEnabled) {
+      // Do nothing.
+    }
+
     @Override
     public void onPlayerError(ExoPlaybackException e) {
       // Do nothing.

testutils/src/main/java/com/google/android/exoplayer2/testutil/Action.java

@@ -411,6 +411,11 @@ public abstract class Action {
 
     }
 
+    @Override
+    public void onShuffleModeEnabledChanged(boolean shuffleModeEnabled) {
+
+    }
+
     @Override
     public void onPlayerError(ExoPlaybackException error) {
 

testutils/src/main/java/com/google/android/exoplayer2/testutil/ExoHostedTest.java

@@ -235,6 +235,11 @@ public abstract class ExoHostedTest implements HostedTest, Player.EventListener,
     // Do nothing.
   }
 
+  @Override
+  public void onShuffleModeEnabledChanged(boolean shuffleModeEnabled) {
+    // Do nothing.
+  }
+
   @Override
   public final void onPlayerError(ExoPlaybackException error) {
     playerWasPrepared = true;

testutils/src/main/java/com/google/android/exoplayer2/testutil/ExoPlayerTestRunner.java

@@ -360,6 +360,11 @@ public final class ExoPlayerTestRunner implements Player.EventListener {
     // Do nothing.
   }
 
+  @Override
+  public void onShuffleModeEnabledChanged(boolean shuffleModeEnabled) {
+    // Do nothing.
+  }
+
   @Override
   public void onPlayerError(ExoPlaybackException error) {
     handleException(exception);