Reduce test flakes by adding effects to multi-sequence playback test.

This test is flaky at p4head, because CompositionPlayer has no logic to
ensure a specific input is used to configure the audio graph. Depending
on which sequence registers input first, it changes the output format
of the media.

By setting effects on the 2nd sequence, both inputs are the same format
and this flakiness is avoided in the test.

PiperOrigin-RevId: 653582441

libraries/transformer/src/test/java/androidx/media3/transformer/CompositionPlayerAudioPlaybackTest.java

@@ -19,6 +19,8 @@
 import static androidx.media3.transformer.TestUtil.FILE_AUDIO_RAW;
 import static androidx.media3.transformer.TestUtil.FILE_AUDIO_RAW_STEREO_48000KHZ;
 import static androidx.media3.transformer.TestUtil.createAudioEffects;
+import static androidx.media3.transformer.TestUtil.createChannelCountChangingAudioProcessor;
+import static androidx.media3.transformer.TestUtil.createSampleRateChangingAudioProcessor;
 import static androidx.media3.transformer.TestUtil.createVolumeScalingAudioProcessor;
 
 import android.content.Context;
@@ -215,6 +217,10 @@ public void multiSequenceCompositionPlayback_outputsCorrectSamples() throws Exce
         new EditedMediaItem.Builder(
                 MediaItem.fromUri(ASSET_URI_PREFIX + FILE_AUDIO_RAW_STEREO_48000KHZ))
             .setDurationUs(348_000L)
+            .setEffects(
+                createAudioEffects(
+                    createSampleRateChangingAudioProcessor(44100),
+                    createChannelCountChangingAudioProcessor(1)))
             .build();
     Composition composition =
         new Composition.Builder(

libraries/transformer/src/test/java/androidx/media3/transformer/TestUtil.java

@@ -79,6 +79,12 @@ public static Effects createAudioEffects(AudioProcessor... audioProcessors) {
         ImmutableList.copyOf(audioProcessors), /* videoEffects= */ ImmutableList.of());
   }
 
+  public static SonicAudioProcessor createSampleRateChangingAudioProcessor(int sampleRate) {
+    SonicAudioProcessor sonicAudioProcessor = new SonicAudioProcessor();
+    sonicAudioProcessor.setOutputSampleRateHz(sampleRate);
+    return sonicAudioProcessor;
+  }
+
   public static SonicAudioProcessor createPitchChangingAudioProcessor(float pitch) {
     SonicAudioProcessor sonicAudioProcessor = new SonicAudioProcessor();
     sonicAudioProcessor.setPitch(pitch);