Ignore stale events in StreamEventCallbackV29.

Despite unregistering the callback and clearing pending Handler
messages, the callback may still receive pending calls if they
are already triggered by the AudioTrack. Instead of asserting
that the track is correct, we should gracefully ignore stale
events.

PiperOrigin-RevId: 463851393

library/core/src/main/java/com/google/android/exoplayer2/audio/DefaultAudioSink.java

@@ -30,6 +30,7 @@ import android.media.AudioTrack;
 import android.media.PlaybackParams;
 import android.media.metrics.LogSessionId;
 import android.os.Handler;
+import android.os.Looper;
 import android.os.SystemClock;
 import android.util.Pair;
 import androidx.annotation.DoNotInline;
@@ -1895,7 +1896,7 @@ public final class DefaultAudioSink implements AudioSink {
     private final AudioTrack.StreamEventCallback callback;
 
     public StreamEventCallbackV29() {
-      handler = new Handler();
+      handler = new Handler(Looper.myLooper());
       // Avoid StreamEventCallbackV29 inheriting directly from AudioTrack.StreamEventCallback as it
       // would cause a NoClassDefFoundError warning on load of DefaultAudioSink for SDK < 29.
       // See: https://github.com/google/ExoPlayer/issues/8058
@@ -1903,7 +1904,10 @@ public final class DefaultAudioSink implements AudioSink {
           new AudioTrack.StreamEventCallback() {
             @Override
             public void onDataRequest(AudioTrack track, int size) {
-              Assertions.checkState(track == audioTrack);
+              if (!track.equals(audioTrack)) {
+                // Stale event.
+                return;
+              }
               if (listener != null && playing) {
                 // Do not signal that the buffer is emptying if not playing as it is a transient
                 // state.
@@ -1913,7 +1917,10 @@ public final class DefaultAudioSink implements AudioSink {
 
             @Override
             public void onTearDown(AudioTrack track) {
-              Assertions.checkState(track == audioTrack);
+              if (!track.equals(audioTrack)) {
+                // Stale event.
+                return;
+              }
               if (listener != null && playing) {
                 // The audio track was destroyed while in use. Thus a new AudioTrack needs to be
                 // created and its buffer filled, which will be done on the next handleBuffer call.